1
|
Bordachar P, Strik M, Ploux S. Left Ventricular Endocardial Pacing: Update and State of the Art. Card Electrophysiol Clin 2022; 14:263-271. [PMID: 35715084 DOI: 10.1016/j.ccep.2021.12.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Initially, left ventricular (LV) endocardial pacing was performed as a bailout procedure after unsuccessful transvenous cardiac resynchronization therapy implantation in the presence of surgical contraindications. Additional possible advantages of endocardial LV pacing are a more physiologic activation, being less arrhythmogenic, more effective on the hemodynamic level, with better thresholds, and without the risk of phrenic stimulation. Different techniques have been proposed to stimulate the LV endocardium in humans, with feasibility and safety studies involving limited numbers of patients. In this review, we will describe the different techniques proposed to allow LV endocardial pacing, the results observed, and then we will discuss the reasons why LV endocardial pacing seems to be out of fashion today and what are the possible perspectives for development.
Collapse
Affiliation(s)
- Pierre Bordachar
- Bordeaux University Hospital (CHU), Cardio-Thoracic Unit, Avenue Magellan, 33600 Pessac, France; IHU Liryc, Electrophysiology and Heart Modeling Institute, Avenue Haut Lévêque, 33600 Pessac, France
| | - Marc Strik
- Bordeaux University Hospital (CHU), Cardio-Thoracic Unit, Avenue Magellan, 33600 Pessac, France; IHU Liryc, Electrophysiology and Heart Modeling Institute, Avenue Haut Lévêque, 33600 Pessac, France.
| | - Sylvain Ploux
- Bordeaux University Hospital (CHU), Cardio-Thoracic Unit, Avenue Magellan, 33600 Pessac, France; IHU Liryc, Electrophysiology and Heart Modeling Institute, Avenue Haut Lévêque, 33600 Pessac, France
| |
Collapse
|
2
|
Abstract
Left ventricular (LV) dP/dtmax provides a sensitive measure of the acute hemodynamic response to cardiac resynchronization therapy (CRT) and can predict reverse remodeling on echocardiography. Its use to guide LV lead placement has been shown to improve outcomes in a multicenter randomized trial. Given the invasive protocol required for measurement, it is unlikely to be universally beneficial for patients undergoing CRT but may be useful for patients who do not respond to conventional CRT, or in those who have borderline indications or risk factors for non-response. In such cases, LV dP/dtmax may help guide LV lead placement, optimize device programming, and select the best alternative method of delivering CRT, such endocardial LV pacing or conduction system pacing.
Collapse
Affiliation(s)
- Mark K Elliott
- School of Biomedical Engineering and Imaging Sciences, King's College London, London, UK; Department of Cardiology, Guy's and St Thomas' NHS Foundation Trust, London, UK.
| | - Vishal S Mehta
- School of Biomedical Engineering and Imaging Sciences, King's College London, London, UK; Department of Cardiology, Guy's and St Thomas' NHS Foundation Trust, London, UK
| | - Christopher A Rinaldi
- School of Biomedical Engineering and Imaging Sciences, King's College London, London, UK; Department of Cardiology, Guy's and St Thomas' NHS Foundation Trust, London, UK
| |
Collapse
|
3
|
Miyazawa AA, Francis DP, Whinnett ZI. Basic Principles of Hemodynamics in Pacing. Card Electrophysiol Clin 2022; 14:133-140. [PMID: 35715072 DOI: 10.1016/j.ccep.2021.12.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Pacing therapy aims to improve overall cardiac function by normalizing cardiac electrical activation. Although hemodynamic measurements allow the impact of cardiac pacing on cardiac function to be quantified, the protocol is crucial to minimize the effect of noise and achieve greater precision. Multiple steps can be undertaken to optimize accuracy of hemodynamic measurements. These include comparing with a reference state, using an average of a set number of beats, making repeated measurements, ensuring all beats are included, and pacing at faster heart rates. These measurements can aid comparison between different pacing modalities and guide optimal programming.
Collapse
Affiliation(s)
- Alejandra A Miyazawa
- National Heart and Lung Institute, Imperial College London, Hammersmith Hospital, Du Cane Road, London W12 0HS, UK
| | - Darrel P Francis
- National Heart and Lung Institute, Imperial College London, Hammersmith Hospital, Du Cane Road, London W12 0HS, UK
| | - Zachary I Whinnett
- National Heart and Lung Institute, Imperial College London, Hammersmith Hospital, Du Cane Road, London W12 0HS, UK.
| |
Collapse
|
4
|
Keene D, Miyazawa AA, Johal M, Arnold AD, Ali N, Saqi KA, March K, Burden L, Francis DP, Whinnett ZI, Shun‐Shin MJ. Optimizing atrio-ventricular delay in pacemakers using potentially implantable physiological biomarkers. Pacing Clin Electrophysiol 2022; 45:461-470. [PMID: 34967945 PMCID: PMC9305784 DOI: 10.1111/pace.14434] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/12/2021] [Revised: 11/25/2021] [Accepted: 12/19/2021] [Indexed: 11/30/2022]
Abstract
BACKGROUND Hemodynamically optimal atrioventricular (AV) delay can be derived by echocardiography or beat-by-beat blood pressure (BP) measurements, but analysis is labor intensive. Laser Doppler perfusion monitoring measures blood flow and can be incorporated into future implantable cardiac devices. We assess whether laser Doppler can be used instead of BP to optimize AV delay. METHODS Fifty eight patients underwent 94 AV delay optimizations with biventricular or His-bundle pacing using laser Doppler and simultaneous noninvasive beat-by-beat BP. Optimal AV delay was defined using a curve of hemodynamic response to switching from AAI (reference state) to DDD (test state) at several AV delays (40-320 ms), with automatic quality control checking precision of the optimum. Five subsequent patients underwent an extended protocol to test the impact of greater numbers of alternations on optimization quality. RESULTS 55/94 optimizations passed quality control resulting in an optimal AV delay on laser Doppler similar to that derived by BP (median absolute deviation 12 ms). An extended protocol with increasing number of replicates consistently improved quality and reduced disagreement between laser Doppler and BP optima. With only five replicates, no optimization passed quality control, and the median absolute deviation would be 29 ms. These improved progressively until at 50 replicates, all optimizations passed quality control and the median absolute deviation was only 13 ms. CONCLUSIONS Laser Doppler perfusion produces hemodynamic optima equivalent to BP. Quality control can be automatic. Adding more replicates, consistently improves quality. Future implantable devices could use such methods to dynamically and reliably optimize AV delays.
Collapse
Affiliation(s)
- Daniel Keene
- National Heart and Lung Institute, Imperial College London, Hammersmith HospitalLondonUK,Imperial College Healthcare NHS Trust, Hammersmith HospitalLondonUK
| | - Alejandra A Miyazawa
- National Heart and Lung Institute, Imperial College London, Hammersmith HospitalLondonUK,Imperial College Healthcare NHS Trust, Hammersmith HospitalLondonUK
| | - Monika Johal
- National Heart and Lung Institute, Imperial College London, Hammersmith HospitalLondonUK
| | - Ahran D Arnold
- National Heart and Lung Institute, Imperial College London, Hammersmith HospitalLondonUK,Imperial College Healthcare NHS Trust, Hammersmith HospitalLondonUK
| | - Nadine Ali
- National Heart and Lung Institute, Imperial College London, Hammersmith HospitalLondonUK,Imperial College Healthcare NHS Trust, Hammersmith HospitalLondonUK
| | - Khulat A Saqi
- National Heart and Lung Institute, Imperial College London, Hammersmith HospitalLondonUK
| | - Katherine March
- National Heart and Lung Institute, Imperial College London, Hammersmith HospitalLondonUK
| | - Leah Burden
- National Heart and Lung Institute, Imperial College London, Hammersmith HospitalLondonUK
| | - Darrel P Francis
- National Heart and Lung Institute, Imperial College London, Hammersmith HospitalLondonUK,Imperial College Healthcare NHS Trust, Hammersmith HospitalLondonUK
| | - Zachary I Whinnett
- National Heart and Lung Institute, Imperial College London, Hammersmith HospitalLondonUK,Imperial College Healthcare NHS Trust, Hammersmith HospitalLondonUK
| | - Matthew J Shun‐Shin
- National Heart and Lung Institute, Imperial College London, Hammersmith HospitalLondonUK,Imperial College Healthcare NHS Trust, Hammersmith HospitalLondonUK
| |
Collapse
|
5
|
Lane ES, Azarmehr N, Jevsikov J, Howard JP, Shun-Shin MJ, Cole GD, Francis DP, Zolgharni M. Multibeat echocardiographic phase detection using deep neural networks. Comput Biol Med 2021; 133:104373. [PMID: 33857775 DOI: 10.1016/j.compbiomed.2021.104373] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2021] [Revised: 03/30/2021] [Accepted: 03/30/2021] [Indexed: 11/27/2022]
Abstract
BACKGROUND Accurate identification of end-diastolic and end-systolic frames in echocardiographic cine loops is important, yet challenging, for human experts. Manual frame selection is subject to uncertainty, affecting crucial clinical measurements, such as myocardial strain. Therefore, the ability to automatically detect frames of interest is highly desirable. METHODS We have developed deep neural networks, trained and tested on multi-centre patient data, for the accurate identification of end-diastolic and end-systolic frames in apical four-chamber 2D multibeat cine loop recordings of arbitrary length. Seven experienced cardiologist experts independently labelled the frames of interest, thereby providing infallible annotations, allowing for observer variability measurements. RESULTS When compared with the ground-truth, our model shows an average frame difference of -0.09 ± 1.10 and 0.11 ± 1.29 frames for end-diastolic and end-systolic frames, respectively. When applied to patient datasets from a different clinical site, to which the model was blind during its development, average frame differences of -1.34 ± 3.27 and -0.31 ± 3.37 frames were obtained for both frames of interest. All detection errors fall within the range of inter-observer variability: [-0.87, -5.51]±[2.29, 4.26] and [-0.97, -3.46]±[3.67, 4.68] for ED and ES events, respectively. CONCLUSIONS The proposed automated model can identify multiple end-systolic and end-diastolic frames in echocardiographic videos of arbitrary length with performance indistinguishable from that of human experts, but with significantly shorter processing time.
Collapse
Affiliation(s)
- Elisabeth S Lane
- School of Computing and Engineering, University of West London, London, United Kingdom.
| | - Neda Azarmehr
- National Heart and Lung Institute, Imperial College, London, United Kingdom
| | - Jevgeni Jevsikov
- School of Computing and Engineering, University of West London, London, United Kingdom
| | - James P Howard
- National Heart and Lung Institute, Imperial College, London, United Kingdom
| | | | - Graham D Cole
- National Heart and Lung Institute, Imperial College, London, United Kingdom
| | - Darrel P Francis
- National Heart and Lung Institute, Imperial College, London, United Kingdom
| | - Massoud Zolgharni
- School of Computing and Engineering, University of West London, London, United Kingdom; National Heart and Lung Institute, Imperial College, London, United Kingdom
| |
Collapse
|
6
|
Latham J, Hicks Y, Yang X, Setchi R, Rainer T. Stable Automatic Envelope Estimation for Noisy Doppler Ultrasound. IEEE TRANSACTIONS ON ULTRASONICS, FERROELECTRICS, AND FREQUENCY CONTROL 2021; 68:465-481. [PMID: 32746225 DOI: 10.1109/tuffc.2020.3011823] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Doppler ultrasound technology is widespread in clinical applications and is principally used for blood flow measurements in the heart, arteries, and veins. A commonly extracted parameter is the maximum velocity envelope. However, current methods of extracting it cannot produce stable envelopes in high noise conditions. This can limit clinical and research applications using the technology. In this article, a new method of automatic envelope estimation is presented. The method can handle challenging signals with high levels of noise and variable envelope shapes. Envelopes are extracted from a Doppler spectrogram image generated directly from the Doppler audio signal, making it less device-dependent than existing image-processing methods. The method's performance is assessed using simulated pulsatile flow, a flow phantom, and in vivo ascending aortic flow measurements and is compared with three state-of-the-art methods. The proposed method is the most accurate in noisy conditions, achieving, on average, for phantom data with signal-to-noise ratios (SNRs) below 10 dB, bias and standard deviation of 0.7% and 3.3% lower than the next-best performing method. In addition, a new method for beat segmentation is proposed. When combined, the two proposed methods exhibited the best performance using in vivo data, producing the least number of incorrectly segmented beats and 8.2% more correctly segmented beats than the next best performing method. The ability of the proposed methods to reliably extract timing indices for cardiac cycles across a range of signal quality is of particular significance for research and monitoring applications.
Collapse
|
7
|
Bachtiger P, Plymen CM, Pabari PA, Howard JP, Whinnett ZI, Opoku F, Janering S, Faisal AA, Francis DP, Peters NS. Artificial Intelligence, Data Sensors and Interconnectivity: Future Opportunities for Heart Failure. Card Fail Rev 2020; 6:e11. [PMID: 32514380 PMCID: PMC7265101 DOI: 10.15420/cfr.2019.14] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/04/2019] [Accepted: 01/23/2020] [Indexed: 11/08/2022] Open
Abstract
A higher proportion of patients with heart failure have benefitted from a wide and expanding variety of sensor-enabled implantable devices than any other patient group. These patients can now also take advantage of the ever-increasing availability and affordability of consumer electronics. Wearable, on- and near-body sensor technologies, much like implantable devices, generate massive amounts of data. The connectivity of all these devices has created opportunities for pooling data from multiple sensors – so-called interconnectivity – and for artificial intelligence to provide new diagnostic, triage, risk-stratification and disease management insights for the delivery of better, more personalised and cost-effective healthcare. Artificial intelligence is also bringing important and previously inaccessible insights from our conventional cardiac investigations. The aim of this article is to review the convergence of artificial intelligence, sensor technologies and interconnectivity and the way in which this combination is set to change the care of patients with heart failure.
Collapse
Affiliation(s)
- Patrik Bachtiger
- Imperial Centre for Cardiac Engineering, National Heart and Lung Institute, Imperial College London, UK
| | - Carla M Plymen
- Department of Cardiology, Imperial College Healthcare NHS Trust, Hammersmith Hospital London, UK
| | - Punam A Pabari
- Department of Cardiology, Imperial College Healthcare NHS Trust, Hammersmith Hospital London, UK
| | - James P Howard
- Imperial Centre for Cardiac Engineering, National Heart and Lung Institute, Imperial College London, UK.,Department of Cardiology, Imperial College Healthcare NHS Trust, Hammersmith Hospital London, UK
| | - Zachary I Whinnett
- Department of Cardiology, Imperial College Healthcare NHS Trust, Hammersmith Hospital London, UK
| | - Felicia Opoku
- IT Department, Imperial College Healthcare NHS London, UK
| | | | - Aldo A Faisal
- Departments of Bioengineering and Computing, Data Science Institute, Imperial College London, UK
| | - Darrel P Francis
- Imperial Centre for Cardiac Engineering, National Heart and Lung Institute, Imperial College London, UK.,Department of Cardiology, Imperial College Healthcare NHS Trust, Hammersmith Hospital London, UK
| | - Nicholas S Peters
- Imperial Centre for Cardiac Engineering, National Heart and Lung Institute, Imperial College London, UK.,Department of Cardiology, Imperial College Healthcare NHS Trust, Hammersmith Hospital London, UK
| |
Collapse
|
8
|
Engels EB, Thibault B, Mangual J, Badie N, McSpadden LC, Calò L, Ritter P, Pappone C, Bode K, Varma N, Prinzen FW. Dynamic atrioventricular delay programming improves ventricular electrical synchronization as evaluated by 3D vectorcardiography. J Electrocardiol 2019; 58:1-6. [PMID: 31677533 DOI: 10.1016/j.jelectrocard.2019.09.026] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2019] [Revised: 09/05/2019] [Accepted: 09/25/2019] [Indexed: 11/25/2022]
Abstract
BACKGROUND Optimal timing of the atrioventricular delay in cardiac resynchronization therapy (CRT) can improve synchrony in patients suffering from heart failure. The purpose of this study was to evaluate the impact of SyncAV™ on electrical synchrony as measured by vectorcardiography (VCG) derived QRS metrics during bi-ventricular (BiV) pacing. METHODS Patients implanted with a cardiac resynchronization therapy (CRT) device and quadripolar left ventricular (LV) lead underwent 12‑lead ECG recordings. VCG metrics, including QRS duration (QRSd) and area, were derived from the ECG by a blinded observer during: intrinsic conduction, BiV with nominal atrioventricular delays (BiV Nominal), and BiV with SyncAV programmed to the optimal offset achieving maximal synchronization (BiV + SyncAV Opt). RESULTS One hundred patients (71% male, 40% ischemic, 65% LBBB, 32 ± 9% ejection fraction) completed VCG assessment. QRSd during intrinsic conduction (166 ± 25 ms) was narrowed successively by BiV Nominal (137 ± 23 ms, p < .05 vs. intrinsic) and BiV + SyncAV Opt (122 ± 22 ms, p < .05 vs. BiV Nominal). Likewise, 3D QRS area during intrinsic conduction (90 ± 42 mV ∗ ms) was reduced by BiV Nominal (65 ± 39 mV ∗ ms, p < .05 vs. intrinsic) and further by BiV + SyncAV Opt (53 ± 30 mV ∗ ms, p = .06 vs. BiV Nominal). CONCLUSION With VCG-based, patient-specific optimization of the programmable offset, SyncAV reduced electrical dyssynchrony beyond conventional CRT.
Collapse
Affiliation(s)
- Elien B Engels
- Department of Physiology, Cardiovascular Research Institute Maastricht, Maastricht, the Netherlands; Department of Medicine, University of Western Ontario, London, Ontario, Canada
| | - Bernard Thibault
- Electrophysiology Service, Montreal Heart Institute, Montreal, Canada
| | | | | | | | - Leonardo Calò
- Department of Cardiology, Policlinico Casilino, Rome, Italy
| | | | - Carlo Pappone
- Department of Electrophysiology, I.R.C.C.S. Policlinico San Donato, San Donato Milanese, Italy
| | - Kerstin Bode
- Department of Electrophysiology, University of Leipzig Heart Center, Leipzig, Germany
| | - Niraj Varma
- Cleveland Clinic, Cleveland, OH, United States
| | - Frits W Prinzen
- Department of Physiology, Cardiovascular Research Institute Maastricht, Maastricht, the Netherlands.
| |
Collapse
|
9
|
Sharp AJ, Sohaib SMA, Shun-Shin MJ, Pabari P, Willson K, Rajkumar C, Hughes AD, Kanagaratnam P, Mayet J, Whinnett ZI, Kyriacou AA, Francis DP. Improving haemodynamic optimization of cardiac resynchronization therapy for heart failure. Physiol Meas 2019; 40:04NT01. [PMID: 30933931 DOI: 10.1088/1361-6579/ab152c] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
OBJECTIVE Optimization of cardiac resynchronization therapy using non-invasive haemodynamic parameters produces reliable optima when performed at high atrial paced heart rates. Here we investigate whether this is a result of increased heart rate or atrial pacing itself. APPROACH Forty-three patients with cardiac resynchronization therapy underwent haemodynamic optimization of atrioventricular (AV) delay using non-invasive beat-to-beat systolic blood pressure in three states: rest (atrial-sensing, 66 ± 11 bpm), slow atrial pacing (73 ± 12 bpm), and fast atrial pacing (94 ± 10 bpm). A 20-patient subset underwent a fourth optimization, during exercise (80 ± 11 bpm). MAIN RESULTS Intraclass correlation coefficient (ICC, quantifying information content mean ±SE) was 0.20 ± 0.02 for resting sensed optimization, 0.45 ± 0.03 for slow atrial pacing (p < 0.0001 versus rest-sensed), and 0.52 ± 0.03 for fast atrial pacing (p = 0.12 versus slow-paced). 78% of the increase in ICC, from sinus rhythm to fast atrial pacing, is achieved by simply atrially pacing just above sinus rate. Atrial pacing increased signal (blood pressure difference between best and worst AV delay) from 6.5 ± 0.6 mmHg at rest to 13.3 ± 1.1 mmHg during slow atrial pacing (p < 0.0001) and 17.2 ± 1.3 mmHg during fast atrial pacing (p = 0.003 versus slow atrial pacing). Atrial pacing reduced noise (average SD of systolic blood pressure measurements) from 4.9 ± 0.4 mmHg at rest to 4.1 ± 0.3 mmHg during slow atrial pacing (p = 0.28). At faster atrial pacing the noise was 4.6 ± 0.3 mmHg (p = 0.69 versus slow-paced, p = 0.90 versus rest-sensed). In the exercise subgroup ICC was 0.14 ± 0.02 (p = 0.97 versus rest-sensed). SIGNIFICANCE Atrial pacing, rather than the increase in heart rate, contributes to ~80% of the observed information content improvement from sinus rhythm to fast atrial pacing. This is predominantly through increase in measured signal.
Collapse
Affiliation(s)
- Alexander J Sharp
- Addenbrooke's Hospital, Cambridge University Hospitals NHS Trust, Hills Rd, Cambridge CB2 0QQ, United Kingdom
| | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
10
|
Cardiac resynchronisation therapy optimisation of interventricular delay by the systolic dyssynchrony index: A comparative, randomised, 12-month follow-up study. Hellenic J Cardiol 2019; 60:16-25. [DOI: 10.1016/j.hjc.2017.11.003] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2017] [Revised: 10/29/2017] [Accepted: 11/01/2017] [Indexed: 11/23/2022] Open
|
11
|
Rowe MK, Kaye GC. Advances in atrioventricular and interventricular optimization of cardiac resynchronization therapy - what's the gold standard? Expert Rev Cardiovasc Ther 2018; 16:183-196. [PMID: 29338475 DOI: 10.1080/14779072.2018.1427582] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
INTRODUCTION Cardiac resynchronization therapy (CRT) is one of the most important advances in heart failure management in the last twenty years. Approximately one-third of patients appear not to respond to therapy. Although there are a number of possible mechanisms for non-response, an important factor is suboptimal atrioventricular (AV) and interventricular (VV) timing intervals. There remains controversy over whether routinely optimizing intervals is necessary and there is no agreed gold standard methodology. Optimization has classically been performed using echocardiography which has limits related to resource use, time-cost and variable reproducibility. Newer optimization methods using device-based sensors and algorithms show promise in reducing heart-failure hospitalization compared with echocardiography. Areas covered: This review outlines the rationale for optimization, the principles of AV and VV optimization, the standard echocardiographic approach and newer device-based algorithms and the evidence base for their use. Expert commentary: The incremental gains of optimization are likely to be real, but small, compared to the overall improvement gained from cardiac resynchronization itself. At this time routine optimization may not be mandatory but should be performed where there is no response to CRT. Device-based optimization algorithms appear to be practical and in some cases, deliver superior clinical outcomes compared to echocardiography.
Collapse
Affiliation(s)
- Matthew K Rowe
- a Department of Cardiology , Princess Alexandra Hospital , Brisbane , Australia.,b Faculty of Medicine , The University of Queensland , Brisbane , Australia
| | - Gerald C Kaye
- a Department of Cardiology , Princess Alexandra Hospital , Brisbane , Australia.,b Faculty of Medicine , The University of Queensland , Brisbane , Australia
| |
Collapse
|
12
|
Engels EB, Strik M, van Middendorp LB, Kuiper M, Vernooy K, Prinzen FW. Prediction of optimal cardiac resynchronization by vectors extracted from electrograms in dyssynchronous canine hearts. J Cardiovasc Electrophysiol 2017; 28:944-951. [PMID: 28467647 DOI: 10.1111/jce.13241] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/16/2017] [Revised: 04/20/2017] [Accepted: 04/20/2017] [Indexed: 11/30/2022]
Abstract
INTRODUCTION Proper optimization of atrioventricular (AV) and interventricular (VV) intervals can improve the response to cardiac resynchronization therapy (CRT). It has been demonstrated that the area of the QRS complex (QRSarea) extracted from the vectorcardiogram can be used as a predictor of optimal CRT-device settings. We explored the possibility of extracting vectors from the electrograms (EGMs) obtained from pacing electrodes and of using these EGM-based vectors (EGMVs) to individually optimize acute hemodynamic CRT response. METHODS AND RESULTS Biventricular pacing was performed in 13 dogs with left bundle branch block (LBBB) of which five also had myocardial infarction (MI), using 100 randomized AV- and VV-settings. Settings providing an acute increase in LV dP/dtmax ≥ 90% of the highest achieved value were defined as optimal. The prediction capability of QRSarea derived from the EGMV (EGMV-QRSarea) was compared with that of QRS duration. EGMV-QRSarea strongly correlated to the change in LV dP/dtmax (R = -0.73 ± 0.19 [LBBB] and -0.66 ± 0.14 [LBBB + MI]), while QRS duration was more poorly related to LV dP/dtmax changes (R = -0.33 ± 0.25 [LBBB] and -0.47 ± 0.39 [LBBB + MI]). This resulted in a better prediction of optimal CRT-device settings by EGMV-QRSarea than by QRS duration (LBBB: AUC = 0.89 [0.86-0.93] vs. 0.76 [0.69-0.83], P < 0.01; LBBB + MI: AUC = 0.91 [0.84-0.99] vs. 0.82 [0.59-1.00], P = 0.20, respectively). CONCLUSION In canine hearts with chronic LBBB with or without MI, the EGMV-QRSarea predicts acute hemodynamic CRT response and identifies optimal AV and VV settings accurately. These data support the potency of EGM-based vectors as a noninvasive, easy and patient-tailored tool to optimize CRT-device settings.
Collapse
Affiliation(s)
- Elien B Engels
- Department of Physiology, Cardiovascular Research Institute Maastricht (CARIM), Maastricht University, Maastricht, the Netherlands
| | - Marc Strik
- Department of Physiology, Cardiovascular Research Institute Maastricht (CARIM), Maastricht University, Maastricht, the Netherlands.,Department of Cardiology, Maastricht University Medical Center, Maastricht, the Netherlands
| | - Lars B van Middendorp
- Department of Physiology, Cardiovascular Research Institute Maastricht (CARIM), Maastricht University, Maastricht, the Netherlands
| | - Marion Kuiper
- Department of Physiology, Cardiovascular Research Institute Maastricht (CARIM), Maastricht University, Maastricht, the Netherlands
| | - Kevin Vernooy
- Department of Physiology, Cardiovascular Research Institute Maastricht (CARIM), Maastricht University, Maastricht, the Netherlands.,Department of Cardiology, Maastricht University Medical Center, Maastricht, the Netherlands
| | - Frits W Prinzen
- Department of Physiology, Cardiovascular Research Institute Maastricht (CARIM), Maastricht University, Maastricht, the Netherlands
| |
Collapse
|
13
|
Sterliński M, Sokal A, Lenarczyk R, Van Heuverswyn F, Rinaldi CA, Vanderheyden M, Khalameizer V, Francis D, Heynens J, Stegemann B, Cornelussen R. In Heart Failure Patients with Left Bundle Branch Block Single Lead MultiSpot Left Ventricular Pacing Does Not Improve Acute Hemodynamic Response To Conventional Biventricular Pacing. A Multicenter Prospective, Interventional, Non-Randomized Study. PLoS One 2016; 11:e0154024. [PMID: 27124724 PMCID: PMC4849737 DOI: 10.1371/journal.pone.0154024] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2016] [Accepted: 04/06/2016] [Indexed: 12/31/2022] Open
Abstract
INTRODUCTION Recent efforts to increase CRT response by multiSPOT pacing (MSP) from multiple bipols on the same left ventricular lead are still inconclusive. AIM The Left Ventricular (LV) MultiSPOTpacing for CRT (iSPOT) study compared the acute hemodynamic response of MSP pacing by using 3 electrodes on a quadripolar lead compared with conventional biventricular pacing (BiV). METHODS Patients with left bundle branch block (LBBB) underwent an acute hemodynamic study to determine the %change in LV+dP/dtmax from baseline atrial pacing compared to the following configurations: BiV pacing with the LV lead in a one of lateral veins, while pacing from the distal, mid, or proximal electrode and all 3 electrodes together (i.e. MSP). All measurements were repeated 4 times at 5 different atrioventricular delays. We also measured QRS-width and individual Q-LV durations. RESULTS Protocol was completed in 24 patients, all with LBBB (QRS width 171±20 ms) and 58% ischemic aetiology. The percentage change in LV+dP/dtmax for MSP pacing was 31.0±3.3% (Mean±SE), which was not significantly superior to any BiV pacing configuration: 28.9±3.2% (LV-distal), 28.3±2.7% (LV-mid), and 29.5±3.0% (LV-prox), respectively. Correlation between LV+dP/dtmax and either QRS-width or Q-LV ratio was poor. CONCLUSIONS In patients with LBBB MultiSPOT LV pacing demonstrated comparable improvement in contractility to best conventional BiV pacing. Optimization of atrioventricular delay is important for the best performance for both BiV and MultiSPOT pacing configurations. TRIAL REGISTRATION ClinicalTrials.gov NTC01883141.
Collapse
Affiliation(s)
- Maciej Sterliński
- The Second Department of Coronary Artery Disease, Institute of Cardiology, Warsaw, Poland
- * E-mail:
| | - Adam Sokal
- Department of Cardiology,Congenital Heart Diseases and Electrotherapy Silesian Center of Heart Disease, Zabrze, Poland
| | - Radosław Lenarczyk
- Department of Cardiology,Congenital Heart Diseases and Electrotherapy Silesian Center of Heart Disease, Zabrze, Poland
| | | | - C. Aldo Rinaldi
- Guys and St Thomas NHS Trust, St Thomas Hospital, London, England
| | | | | | - Darrel Francis
- Faculty of Medicine, Imperial College Healthcare NHS Trust, London, England
| | - Joeri Heynens
- Bakken Research Center, Medtronic, Maastricht, The Netherlands
| | | | | |
Collapse
|
14
|
Abstract
Echocardiography is used in cardiac resynchronisation therapy (CRT) to assess cardiac function, and in particular left ventricular (LV) volumetric status, and prediction of response. Despite its widespread applicability, LV volumes determined by echocardiography have inherent measurement errors, interobserver and intraobserver variability, and discrepancies with the gold standard magnetic resonance imaging. Echocardiographic predictors of CRT response are based on mechanical dyssynchrony. However, parameters are mainly tested in single-centre studies or lack feasibility. Speckle tracking echocardiography can guide LV lead placement, improving volumetric response and clinical outcome by guiding lead positioning towards the latest contracting segment. Results on optimisation of CRT device settings using echocardiographic indices have so far been rather disappointing, as results suffer from noise. Defining response by echocardiography seems valid, although re-assessment after 6 months is advisable, as patients can show both continuous improvement as well as deterioration after the initial response. Three-dimensional echocardiography is interesting for future implications, as it can determine volume, dyssynchrony and viability in a single recording, although image quality needs to be adequate. Deformation patterns from the septum and the derived parameters are promising, although validation in a multicentre trial is required. We conclude that echocardiography has a pivotal role in CRT, although clinicians should know its shortcomings.
Collapse
|
15
|
Niederer S, Walker C, Crozier A, Hyde ER, Blazevic B, Behar JM, Claridge S, Sohal M, Shetty A, Jackson T, Rinaldi C. The impact of beat-to-beat variability in optimising the acute hemodynamic response in cardiac resynchronisation therapy. CLINICAL TRIALS AND REGULATORY SCIENCE IN CARDIOLOGY 2015; 12:18-22. [PMID: 26844303 PMCID: PMC4696127 DOI: 10.1016/j.ctrsc.2015.10.004] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/14/2015] [Accepted: 10/19/2015] [Indexed: 01/27/2023]
Abstract
BACKGROUND Acute indicators of response to cardiac resynchronisation therapy (CRT) are critical for developing lead optimisation algorithms and evaluating novel multi-polar, multi-lead and endocardial pacing protocols. Accounting for beat-to-beat variability in measures of acute haemodynamic response (AHR) may help clinicians understand the link between acute measurements of cardiac function and long term clinical outcome. METHODS AND RESULTS A retrospective study of invasive pressure tracings from 38 patients receiving an acute pacing and electrophysiological study was performed. 602 pacing protocols for left ventricle (LV) (n = 38), atria-ventricle (AV) (n = 9), ventricle-ventricle (VV) (n = 12) and endocardial (ENDO) (n = 8) optimisation were performed. AHR was measured as the maximal rate of LV pressure development (dP/dtMx) for each beat. The range of the 95% confidence interval (CI) of mean AHR was ~ 7% across all optimisation protocols compared with the reported CRT response cut off value of 10%. A single clear optimal protocol was identifiable in 61%, 22%, 25% and 50% for LV, AV, VV and ENDO optimisation cases, respectively. A level of service (LOS) optimisation that aimed to maximise the expected AHR 5th percentile, minimising variability and maximising AHR, led to distinct optimal protocols from conventional mean AHR optimisation in 34%, 78%, 67% and 12.5% of LV, AV, VV and ENDO optimisation cases, respectively. CONCLUSION The beat-to-beat variation in AHR is significant in the context of CRT cut off values. A LOS optimisation offers a novel index to identify the optimal pacing site that accounts for both the mean and variation of the baseline measurement and pacing protocol.
Collapse
Affiliation(s)
- Steven Niederer
- Division of Imaging Sciences and Biomedical Engineering, King's College London, UK
| | - Cameron Walker
- Department of Engineering Science, University of Auckland, New Zealand
| | - Andrew Crozier
- Division of Imaging Sciences and Biomedical Engineering, King's College London, UK
| | - Eoin R. Hyde
- Division of Imaging Sciences and Biomedical Engineering, King's College London, UK
| | - Bojan Blazevic
- Division of Imaging Sciences and Biomedical Engineering, King's College London, UK
| | - Jonathan M. Behar
- Cardiovascular Department, Guy's and St. Thomas' NHS Foundation Trust, London, UK
| | - Simon Claridge
- Cardiovascular Department, Guy's and St. Thomas' NHS Foundation Trust, London, UK
| | - Manav Sohal
- Cardiovascular Department, Guy's and St. Thomas' NHS Foundation Trust, London, UK
| | - Anoop Shetty
- Cardiovascular Department, Guy's and St. Thomas' NHS Foundation Trust, London, UK
| | - Tom Jackson
- Cardiovascular Department, Guy's and St. Thomas' NHS Foundation Trust, London, UK
| | - Christopher Rinaldi
- Cardiovascular Department, Guy's and St. Thomas' NHS Foundation Trust, London, UK
| |
Collapse
|
16
|
Abstract
Cardiac resynchronisation therapy (CRT) is an effective intervention for appropriately selected patients with heart failure, but exactly how it works is uncertain. Recent data suggest that much, or perhaps most, of the benefits of CRT are not delivered by re-coordinating left ventricular dyssynchrony. Atrio-ventricular resynchronization, reduction in mitral regurgitation and prevention of bradycardia are other potential mechanisms of benefit that will vary from one patient to the next and over time. Because there is no single therapeutic target, it is unlikely that any single measure will accurately predict benefit. The only clinical characteristic that appears to be a useful predictor of the benefits of CRT is a QRS duration of >140 ms. Many new approaches are being developed to try to improve the effectiveness of and extend the indications for CRT. These include smart pacing algorithms, better pacing-site targeting, new sensors, multipoint pacing, remote device monitoring and leadless endocardial pacing. Whether CRT is effective in patients with atrial fibrillation or whether adding a defibrillator function to CRT improves prognosis awaits further evidence.
Collapse
|
17
|
Sohaib SMA, Kyriacou A, Jones S, Manisty CH, Mayet J, Kanagaratnam P, Peters NS, Hughes AD, Whinnett ZI, Francis DP. Evidence that conflict regarding size of haemodynamic response to interventricular delay optimization of cardiac resynchronization therapy may arise from differences in how atrioventricular delay is kept constant. Europace 2015; 17:1823-33. [PMID: 25855674 PMCID: PMC4700730 DOI: 10.1093/europace/euu374] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2014] [Accepted: 12/01/2014] [Indexed: 01/21/2023] Open
Abstract
Aims Whether adjusting interventricular (VV) delay changes haemodynamic efficacy of cardiac resynchronization therapy (CRT) is controversial, with conflicting results. This study addresses whether the convention for keeping atrioventricular (AV) delay constant during VV optimization might explain these conflicts. Method and results Twenty-two patients in sinus rhythm with existing CRT underwent VV optimization using non-invasive systolic blood pressure. Interventricular optimization was performed with four methods for keeping the AV delay constant: (i) atrium and left ventricle delay kept constant, (ii) atrium and right ventricle delay kept constant, (iii) time to the first-activated ventricle kept constant, and (iv) time to the second-activated ventricle kept constant. In 11 patients this was performed with AV delay of 120 ms, and in 11 at AV optimum. At AV 120 ms, time to the first ventricular lead (left or right) was the overwhelming determinant of haemodynamics (13.75 mmHg at ±80 ms, P < 0.001) with no significant effect of time to second lead (0.47 mmHg, P = 0.50), P < 0.001 for difference. At AV optimum, time to first ventricular lead again had a larger effect (5.03 mmHg, P < 0.001) than time to second (2.92 mmHg, P = 0.001), P = 0.02 for difference. Conclusion Time to first ventricular activation is the overwhelming determinant of circulatory function, regardless of whether this is the left or right ventricular lead. If this is kept constant, the effect of changing time to the second ventricle is small or nil, and is not beneficial. In practice, it may be advisable to leave VV delay at zero. Specifying how AV delay is kept fixed might make future VV delay research more enlightening.
Collapse
Affiliation(s)
- S M Afzal Sohaib
- International Centre for Circulatory Health, Imperial College London, 59-61 North Wharf Road, London W2 1LA, UK
| | - Andreas Kyriacou
- International Centre for Circulatory Health, Imperial College London, 59-61 North Wharf Road, London W2 1LA, UK
| | - Siana Jones
- International Centre for Circulatory Health, Imperial College London, 59-61 North Wharf Road, London W2 1LA, UK
| | - Charlotte H Manisty
- International Centre for Circulatory Health, Imperial College London, 59-61 North Wharf Road, London W2 1LA, UK
| | - Jamil Mayet
- International Centre for Circulatory Health, Imperial College London, 59-61 North Wharf Road, London W2 1LA, UK
| | - Prapa Kanagaratnam
- International Centre for Circulatory Health, Imperial College London, 59-61 North Wharf Road, London W2 1LA, UK
| | - Nicholas S Peters
- International Centre for Circulatory Health, Imperial College London, 59-61 North Wharf Road, London W2 1LA, UK
| | - Alun D Hughes
- International Centre for Circulatory Health, Imperial College London, 59-61 North Wharf Road, London W2 1LA, UK
| | - Zachary I Whinnett
- International Centre for Circulatory Health, Imperial College London, 59-61 North Wharf Road, London W2 1LA, UK
| | - Darrel P Francis
- International Centre for Circulatory Health, Imperial College London, 59-61 North Wharf Road, London W2 1LA, UK
| |
Collapse
|
18
|
van Deursen CJM, Wecke L, van Everdingen WM, Ståhlberg M, Janssen MHG, Braunschweig F, Bergfeldt L, Crijns HJGM, Vernooy K, Prinzen FW. Vectorcardiography for optimization of stimulation intervals in cardiac resynchronization therapy. J Cardiovasc Transl Res 2015; 8:128-37. [PMID: 25743446 PMCID: PMC4382533 DOI: 10.1007/s12265-015-9615-7] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/20/2014] [Accepted: 02/12/2015] [Indexed: 11/26/2022]
Abstract
Current optimization of atrioventricular (AV) and interventricular (VV) intervals in cardiac resynchronization therapy (CRT) is time consuming and subject to noise. We aimed to prove the principle that the best hemodynamic effect of CRT is achieved by cancelation of opposing electrical forces, detectable from the QRS morphology in the 3D vectorcardiogram (VCG). Different degrees of left (LV) and right ventricular (RV) pre-excitation were induced, using variation in AV intervals during LV pacing in 20 patients with left bundle branch block (LBBB) and variation in VV intervals during biventricular pacing in 18 patients with complete AV block or atrial fibrillation. The smallest QRS vector area identified stimulation intervals with minimal systolic stretch (median difference [IQR] 20 ms [−20, 20 ms] and maximal hemodynamic response (10 ms [−20, 40 ms]). Reliability of VCG measurements was superior to hemodynamic measurements. This study proves the principle that VCG analysis may allow easy and reliable optimization of stimulation intervals in CRT patients.
Collapse
Affiliation(s)
- Caroline J M van Deursen
- Departments of Physiology, Cardiovascular Research Institute Maastricht, Maastricht, The Netherlands
| | | | | | | | | | | | | | | | | | | |
Collapse
|
19
|
Sagara K. Ventriculoventricular delay optimization of a cardiac resynchronization device. J Arrhythm 2014. [DOI: 10.1016/j.joa.2014.03.013] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023] Open
|
20
|
Finegold J, Bordachar P, Kyriacou A, Sohaib SMA, Kanagaratnam P, Ploux S, Lim B, Peters N, Davies W, Ritter P, Francis DP, Whinnett ZI. Atrioventricular delay optimization of cardiac resynchronisation therapy: comparison of non-invasive blood pressure with invasive haemodynamic measures. Int J Cardiol 2014; 180:221-2. [PMID: 25463371 DOI: 10.1016/j.ijcard.2014.11.129] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/18/2014] [Revised: 11/14/2014] [Accepted: 11/22/2014] [Indexed: 10/24/2022]
Affiliation(s)
- Judith Finegold
- International Centre for Circulatory Health, National Heart and Lung Institute, London, UK
| | | | - Andreas Kyriacou
- International Centre for Circulatory Health, National Heart and Lung Institute, London, UK
| | - S M Afzal Sohaib
- International Centre for Circulatory Health, National Heart and Lung Institute, London, UK
| | - Prapa Kanagaratnam
- International Centre for Circulatory Health, National Heart and Lung Institute, London, UK
| | | | - Boon Lim
- International Centre for Circulatory Health, National Heart and Lung Institute, London, UK
| | - Nicholas Peters
- International Centre for Circulatory Health, National Heart and Lung Institute, London, UK
| | - Wyn Davies
- International Centre for Circulatory Health, National Heart and Lung Institute, London, UK
| | | | - Darrel P Francis
- International Centre for Circulatory Health, National Heart and Lung Institute, London, UK.
| | - Zachary I Whinnett
- International Centre for Circulatory Health, National Heart and Lung Institute, London, UK
| |
Collapse
|
21
|
Vernooy K, van Deursen CJM, Strik M, Prinzen FW. Strategies to improve cardiac resynchronization therapy. Nat Rev Cardiol 2014; 11:481-93. [PMID: 24839977 DOI: 10.1038/nrcardio.2014.67] [Citation(s) in RCA: 57] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Cardiac resynchronization therapy (CRT) emerged 2 decades ago as a useful form of device therapy for heart failure associated with abnormal ventricular conduction, indicated by a wide QRS complex. In this Review, we present insights into how to achieve the greatest benefits with this pacemaker therapy. Outcomes from CRT can be improved by appropriate patient selection, careful positioning of right and left ventricular pacing electrodes, and optimal timing of electrode stimulation. Left bundle branch block (LBBB), which can be detected on an electrocardiogram, is the predominant substrate for CRT, and patients with this conduction abnormality yield the most benefit. However, other features, such as QRS morphology, mechanical dyssynchrony, myocardial scarring, and the aetiology of heart failure, might also determine the benefit of CRT. No single left ventricular pacing site suits all patients, but a late-activated site, during either the intrinsic LBBB rhythm or right ventricular pacing, should be selected. Positioning the lead inside a scarred region substantially impairs outcomes. Optimization of stimulation intervals improves cardiac pump function in the short term, but CRT procedures must become easier and more reliable, perhaps with the use of electrocardiographic measures, to improve long-term outcomes.
Collapse
Affiliation(s)
- Kevin Vernooy
- Department of Cardiology, Maastricht University Medical Center, PO Box 5800, 6202 AZ Maastricht, Netherlands
| | | | - Marc Strik
- Department of Cardiology, Maastricht University Medical Center, PO Box 5800, 6202 AZ Maastricht, Netherlands
| | - Frits W Prinzen
- Department of Physiology, Maastricht University, PO Box 616, 6200 MD Maastricht, Netherlands
| |
Collapse
|
22
|
Zolgharni M, Dhutia NM, Cole GD, Bahmanyar MR, Jones S, Sohaib SMA, Tai SB, Willson K, Finegold JA, Francis DP. Automated aortic Doppler flow tracing for reproducible research and clinical measurements. IEEE TRANSACTIONS ON MEDICAL IMAGING 2014; 33:1071-1082. [PMID: 24770912 DOI: 10.1109/tmi.2014.2303782] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
In clinical practice, echocardiographers are often unkeen to make the significant time investment to make additional multiple measurements of Doppler velocity. Main hurdle to obtaining multiple measurements is the time required to manually trace a series of Doppler traces. To make it easier to analyze more beats, we present the description of an application system for automated aortic Doppler envelope quantification, compatible with a range of hardware platforms. It analyses long Doppler strips, spanning many heartbeats, and does not require electrocardiogram to separate individual beats. We tested its measurement of velocity-time-integral and peak-velocity against the reference standard defined as the average of three experts who each made three separate measurements. The automated measurements of velocity-time-integral showed strong correspondence (R(2) = 0.94) and good Bland-Altman agreement (SD = 1.39 cm) with the reference consensus expert values, and indeed performed as well as the individual experts ( R(2) = 0.90 to 0.96, SD = 1.05 to 1.53 cm). The same performance was observed for peak-velocities; ( R(2) = 0.98, SD = 3.07 cm/s) and ( R(2) = 0.93 to 0.98, SD = 2.96 to 5.18 cm/s). This automated technology allows > 10 times as many beats to be analyzed compared to the conventional manual approach. This would make clinical and research protocols more precise for the same operator effort.
Collapse
|
23
|
Whinnett ZI, Sohaib SMA, Jones S, Kyriacou A, March K, Coady E, Mayet J, Hughes AD, Frenneaux M, Francis DP. British randomised controlled trial of AV and VV optimization ("BRAVO") study: rationale, design, and endpoints. BMC Cardiovasc Disord 2014; 14:42. [PMID: 24693953 PMCID: PMC3992145 DOI: 10.1186/1471-2261-14-42] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2014] [Accepted: 03/21/2014] [Indexed: 11/25/2022] Open
Abstract
Background Echocardiographic optimization of pacemaker settings is the current standard of care for patients treated with cardiac resynchronization therapy. However, the process requires considerable time of expert staff. The BRAVO study is a non-inferiority trial comparing echocardiographic optimization of atrioventricular (AV) and interventricular (VV) delay with an alternative method using non-invasive blood pressure monitoring that can be automated to consume less staff resources. Methods/Design BRAVO is a multi-centre, randomized, cross-over, non-inferiority trial of 400 patients with a previously implanted cardiac resynchronization device. Patients are randomly allocated to six months in each arm. In the echocardiographic arm, AV delay is optimized using the iterative method and VV delay by maximizing LVOT VTI. In the haemodynamic arm AV and VV delay are optimized using non-invasive blood pressure measured using finger photoplethysmography. At the end of each six month arm, patients undergo the primary outcome measure of objective exercise capacity, quantified as peak oxygen uptake (VO2) on a cardiopulmonary exercise test. Secondary outcome measures are echocardiographic measurement of left ventricular remodelling, quality of life score and N-terminal pro B-type Natriuretic Peptide (NT-pro BNP). The study is scheduled to complete recruitment in December 2013 and to complete follow up in December 2014. Discussion If exercise capacity is non-inferior with haemodynamic optimization compared with echocardiographic optimization, it would be proof of concept that haemodynamic optimization is an acceptable alternative which has the potential to be more easily implemented. Trial registration Clinicaltrials.gov NCT01258829
Collapse
Affiliation(s)
- Zachary I Whinnett
- International Centre for Circulatory Health, National Heart and Lung Institute, Imperial College London, 59-61 North Wharf Road, London W2 1LA, UK.
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
24
|
Affiliation(s)
- Frits W. Prinzen
- From the Departments of Physiology (F.W.P.) and Cardiology (K.V.), Cardiovascular Research Institute Maastricht, Maastricht, The Netherlands; and the Division of Cardiology, Fondazione Cardiocentro Ticino, Lugano, Switzerland (A.A.)
| | - Kevin Vernooy
- From the Departments of Physiology (F.W.P.) and Cardiology (K.V.), Cardiovascular Research Institute Maastricht, Maastricht, The Netherlands; and the Division of Cardiology, Fondazione Cardiocentro Ticino, Lugano, Switzerland (A.A.)
| | - Angelo Auricchio
- From the Departments of Physiology (F.W.P.) and Cardiology (K.V.), Cardiovascular Research Institute Maastricht, Maastricht, The Netherlands; and the Division of Cardiology, Fondazione Cardiocentro Ticino, Lugano, Switzerland (A.A.)
| |
Collapse
|
25
|
Sohaib SMA, Whinnett ZI, Ellenbogen KA, Stellbrink C, Quinn TA, Bogaard MD, Bordachar P, van Gelder BM, van Geldorp IE, Linde C, Meine M, Prinzen FW, Turcott RG, Spotnitz HM, Wichterle D, Francis DP. Cardiac resynchronisation therapy optimisation strategies: systematic classification, detailed analysis, minimum standards and a roadmap for development and testing. Int J Cardiol 2013; 170:118-31. [PMID: 24239155 DOI: 10.1016/j.ijcard.2013.10.069] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/02/2013] [Revised: 09/19/2013] [Accepted: 10/19/2013] [Indexed: 01/23/2023]
Abstract
In this article an international group of CRT specialists presents a comprehensive classification system for present and future schemes for optimising CRT. This system is neutral to the measurement technology used, but focuses on little-discussed quantitative physiological requirements. We then present a rational roadmap for reliable cost-effective development and evaluation of schemes. A widely recommended approach for AV optimisation is to visually select the ideal pattern of transmitral Doppler flow. Alternatively, one could measure a variable (such as Doppler velocity time integral) and "pick the highest". More complex would be to make measurements across a range of settings and "fit a curve". In this report we provide clinicians with a critical approach to address any recommendations presented to them, as they may be many, indistinct and conflicting. We present a neutral scientific analysis of each scheme, and equip the reader with simple tools for critical evaluation. Optimisation protocols should deliver: (a) singularity, with only one region of optimality rather than several; (b) blinded test-retest reproducibility; (c) plausibility; (d) concordance between independent methods; and (e) transparency, with all steps open to scrutiny. This simple information is still not available for many optimisation schemes. Clinicians developing the habit of asking about each property in turn will find it easier to win now down the broad range of protocols currently promoted. Expectation of a sophisticated enquiry from the clinical community will encourage optimisation protocol-designers to focus on testing early (and cheaply) the basic properties that are vital for any chance of long term efficacy.
Collapse
Affiliation(s)
-
- National Heart & Lung Institute, Imperial College London, UK.
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
26
|
Kyriacou A, Pabari PA, Mayet J, Peters NS, Davies DW, Lim PB, Lefroy D, Hughes AD, Kanagaratnam P, Francis DP, Whinnett ZI. Cardiac resynchronization therapy and AV optimization increase myocardial oxygen consumption, but increase cardiac function more than proportionally. Int J Cardiol 2013; 171:144-52. [PMID: 24332598 PMCID: PMC3919205 DOI: 10.1016/j.ijcard.2013.10.026] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/28/2013] [Revised: 09/08/2013] [Accepted: 10/07/2013] [Indexed: 11/28/2022]
Abstract
BACKGROUND The mechanoenergetic effects of atrioventricular delay optimization during biventricular pacing ("cardiac resynchronization therapy", CRT) are unknown. METHODS Eleven patients with heart failure and left bundle branch block (LBBB) underwent invasive measurements of left ventricular (LV) developed pressure, aortic flow velocity-time-integral (VTI) and myocardial oxygen consumption (MVO2) at 4 pacing states: biventricular pacing (with VV 0 ms) at AVD 40 ms (AV-40), AVD 120 ms (AV-120, a common nominal AV delay), at their pre-identified individualised haemodynamic optimum (AV-Opt); and intrinsic conduction (LBBB). RESULTS AV-120, relative to LBBB, increased LV developed pressure by a mean of 11(SEM 2)%, p=0.001, and aortic VTI by 11(SEM 3)%, p=0.002, but also increased MVO2 by 11(SEM 5)%, p=0.04. AV-Opt further increased LV developed pressure by a mean of 2(SEM 1)%, p=0.035 and aortic VTI by 4(SEM 1)%, p=0.017. MVO2 trended further up by 7(SEM 5)%, p=0.22. Mechanoenergetics at AV-40 were no different from LBBB. The 4 states lay on a straight line for Δexternal work (ΔLV developed pressure × Δaortic VTI) against ΔMVO2, with slope 1.80, significantly >1 (p=0.02). CONCLUSIONS Biventricular pacing and atrioventricular delay optimization increased external cardiac work done but also myocardial oxygen consumption. Nevertheless, the increase in cardiac work was ~80% greater than the increase in oxygen consumption, signifying an improvement in cardiac mechanoenergetics. Finally, the incremental effect of optimization on external work was approximately one-third beyond that of nominal AV pacing, along the same favourable efficiency trajectory, suggesting that AV delay dominates the biventricular pacing effect - which may therefore not be mainly "resynchronization".
Collapse
Affiliation(s)
- Andreas Kyriacou
- International Centre for Circulatory Health, National Heart and Lung Institute, Imperial College London, UK
| | - Punam A Pabari
- International Centre for Circulatory Health, National Heart and Lung Institute, Imperial College London, UK
| | - Jamil Mayet
- International Centre for Circulatory Health, National Heart and Lung Institute, Imperial College London, UK
| | - Nicholas S Peters
- International Centre for Circulatory Health, National Heart and Lung Institute, Imperial College London, UK
| | - D Wyn Davies
- International Centre for Circulatory Health, National Heart and Lung Institute, Imperial College London, UK
| | - P Boon Lim
- International Centre for Circulatory Health, National Heart and Lung Institute, Imperial College London, UK
| | - David Lefroy
- International Centre for Circulatory Health, National Heart and Lung Institute, Imperial College London, UK
| | - Alun D Hughes
- International Centre for Circulatory Health, National Heart and Lung Institute, Imperial College London, UK
| | - Prapa Kanagaratnam
- International Centre for Circulatory Health, National Heart and Lung Institute, Imperial College London, UK
| | - Darrel P Francis
- International Centre for Circulatory Health, National Heart and Lung Institute, Imperial College London, UK.
| | - Zachary I Whinnett
- International Centre for Circulatory Health, National Heart and Lung Institute, Imperial College London, UK
| |
Collapse
|
27
|
Ulč I, Vančura V. Optimization of pacing intervals in cardiac resynchronization therapy. COR ET VASA 2013. [DOI: 10.1016/j.crvasa.2013.06.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
|
28
|
Cardiac resynchronization therapy mechanisms in atrial fibrillation. Heart Fail Clin 2013; 9:475-88, ix. [PMID: 24054480 DOI: 10.1016/j.hfc.2013.07.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
This article examines how to assess the reliability of potential techniques for performing optimization of biventricular pacemakers in patients with atrial fibrillation. It explores the magnitude of improvement that is likely to be obtained with the optimization of biventricular pacing in this clinical setting and discusses the lessons that can be learned with regard to the mechanisms of action of biventricular pacing in the general heart failure population.
Collapse
|
29
|
Raphael CE, Kyriacou A, Jones S, Pabari P, Cole G, Baruah R, Hughes AD, Francis DP. Multinational evaluation of the interpretability of the iterative method of optimisation of AV delay for CRT. Int J Cardiol 2013; 168:407-13. [DOI: 10.1016/j.ijcard.2012.09.097] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/12/2011] [Revised: 09/12/2012] [Accepted: 09/16/2012] [Indexed: 11/25/2022]
|
30
|
Cardiac resynchronization therapy is certainly cardiac therapy, but how much resynchronization and how much atrioventricular delay optimization? Heart Fail Rev 2013; 17:727-36. [PMID: 21796453 PMCID: PMC3474907 DOI: 10.1007/s10741-011-9271-1] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Cardiac resynchronization therapy has become a standard therapy for patients who are refractory to optimal medical therapy and fulfill the criteria of QRS >120 ms, ejection fraction <35% and NYHA class II, III or IV. Unless there is some other heretofore unrecognized effect of pacing, the benefits of atrio-biventricular pacing on hard outcomes observed in randomized trials can only be attributed to the physiological changes it induces such as increases in cardiac output and/or reduction in myocardial oxygen consumption leading to an improvement in cardiac function efficiency. The term “Cardiac Resynchronization Therapy” for biventricular pacing presupposes that restoration of synchrony (simultaneity of timing) between left and right ventricles and/or between walls of the left ventricle is the mechanism of benefit. But could a substantial proportion of these benefits arise not from ventricular resynchronization but from favorable shortening of AV delay (“AV optimization”) which cannot be termed “resynchronization” unless the meaning of the word is stretched to cover any change in timing, thus, rendering the word almost meaningless. Here, we examine the evidence on the relative balance of resynchronization and AV delay shortening as contributors to the undoubted clinical efficacy of CRT.
Collapse
|
31
|
Whinnett ZI, Francis DP, Denis A, Willson K, Pascale P, van Geldorp I, De Guillebon M, Ploux S, Ellenbogen K, Haïssaguerre M, Ritter P, Bordachar P. Comparison of different invasive hemodynamic methods for AV delay optimization in patients with cardiac resynchronization therapy: implications for clinical trial design and clinical practice. Int J Cardiol 2013; 168:2228-37. [PMID: 23481908 PMCID: PMC3819984 DOI: 10.1016/j.ijcard.2013.01.216] [Citation(s) in RCA: 55] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/07/2012] [Accepted: 01/18/2013] [Indexed: 11/28/2022]
Abstract
Background Reproducibility and hemodynamic efficacy of optimization of AV delay (AVD) of cardiac resynchronization therapy (CRT) using invasive LV dp/dtmax are unknown. Method and results 25 patients underwent AV delay (AVD) optimisation twice, using continuous left ventricular (LV) dp/dtmax, systolic blood pressure (SBP) and pulse pressure (PP). We compared 4 protocols for comparing dp/dtmax between AV delays:Immediate absolute: mean of 10 s recording of dp/dtmax acquired immediately after programming the tested AVD, Delayed absolute: mean of 10 s recording acquired 30 s after programming AVD, Single relative: relative difference between reference AVD and the tested AVD, Multiple relative: averaged difference, from multiple alternations between reference and tested AVD.
We assessed for dp/dtmax, LVSBP and LVPP, test–retest reproducibility of the optimum. Optimization using immediate absolute dp/dtmax had poor reproducibility (SDD of replicate optima = 41 ms; R2 = 0.45) as did delayed absolute (SDD 39 ms; R2 = 0.50). Multiple relative had better reproducibility: SDD 23 ms, R2 = 0.76, and (p < 0.01 by F test). Compared with AAI pacing, the hemodynamic increment from CRT, with the nominal AV delay was LVSBP 2% and LVdp/dtmax 5%, while CRT with pre-determined optimal AVD gave 6% and 9% respectively. Conclusions Because of inevitable background fluctuations, optimization by absolute dp/dtmax has poor same-day reproducibility, unsuitable for clinical or research purposes. Reproducibility is improved by comparing to a reference AVD and making multiple consecutive measurements. More than 6 measurements would be required for even more precise optimization — and might be advisable for future study designs. With optimal AVD, instead of nominal, the hemodynamic increment of CRT is approximately doubled.
Collapse
Affiliation(s)
- Zachary I Whinnett
- Hôpital du Haut-Lévèque, Pessac, France; International Centre for Circulatory Health, National Heart and Lung Institute, Imperial College London, UK.
| | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
32
|
Francis DP. How to reliably deliver narrow individual-patient error bars for optimization of pacemaker AV or VV delay using a “pick-the-highest” strategy with haemodynamic measurements. Int J Cardiol 2013; 163:221-225. [DOI: 10.1016/j.ijcard.2012.03.128] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/06/2012] [Accepted: 03/12/2012] [Indexed: 11/16/2022]
|
33
|
Bogaard MD, Meine M, Doevendans PA. Programmed versus effective VV delay during CRT optimization: when what you see is not what you get. PACING AND CLINICAL ELECTROPHYSIOLOGY: PACE 2013; 36:403-9. [PMID: 23305237 DOI: 10.1111/pace.12065] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/23/2012] [Revised: 10/24/2012] [Accepted: 10/26/2012] [Indexed: 11/27/2022]
Abstract
BACKGROUND In cardiac resynchronization therapy (CRT) devices, the interventricular (VV) delay denotes the time interval between left (LV) and right ventricular (RV) pacing. This study aimed to determine the proportion of patients in whom the effective VV delay (VVeff , delay between LV and RV depolarization, being induced either by pacing or intrinsic conduction) is different from the programmed VV delay during a standard VV delay optimization procedure. METHODS Thirty-three patients with heart failure and left bundle branch block configuration without total atrioventricular (AV) block receiving CRT were prospectively included. VVeff was calculated from intrinsic AV intervals, programmed optimal AV delay, and programming system. Intrinsic AV intervals were measured on intracardiac electrograms. The optimal AV and VV delays were determined by highest increase in maximum rate of LV pressure rise (dP/dtmax ). VV delays of 20-80 ms LV and RV preactivation were tested. RESULTS Calculated maximum possible VVeff was shorter than 80 ms LV preactivation in up to 46% of patients and shorter than 40 ms LV preactivation in up to 3% of the patients. These proportions were 6% and 0% during 80 and 40 ms RV preactivation, respectively. CONCLUSIONS In CRT patients with left bundle branch block without total AV block, the effective VV delay is shorter than the programmed VV delay during a standard optimization procedure in approximately half of the patients and this phenomenon is encountered predominantly during LV preactivation by 40 ms or more. Calculation of the individual maximum VVeff in advance can shorten the VV delay optimization procedure.
Collapse
Affiliation(s)
- Margot D Bogaard
- Department of Cardiology, University Medical Center Utrecht, Utrecht, The Netherlands.
| | | | | |
Collapse
|
34
|
Stegemann B, Francis DP. Atrioventricular and interventricular delay optimization and response quantification in biventricular pacing: arrival of reliable clinical algorithms and research protocols, and how to distinguish them from unreliable counterparts. Europace 2012; 14:1679-83. [DOI: 10.1093/europace/eus242] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
|
35
|
Shanmugam N, Prada-Delgado O, Campos AG, Grimster A, Valencia O, Baltabaeva A, Jones S, Anderson L. Rate-adaptive AV delay and exercise performance following cardiac resynchronization therapy. Heart Rhythm 2012; 9:1815-21. [PMID: 22772135 DOI: 10.1016/j.hrthm.2012.07.001] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/27/2012] [Indexed: 11/30/2022]
Affiliation(s)
- Nesan Shanmugam
- Department of Cardiology, St George's Healthcare NHS Trust, London, United Kingdom.
| | | | | | | | | | | | | | | |
Collapse
|
36
|
Nijjer SS, Pabari PA, Stegemann B, Palmieri V, Leyva F, Linde C, Freemantle N, Davies JE, Hughes AD, Francis DP. The Limit of Plausibility for Predictors of Response: Application to Biventricular Pacing. JACC Cardiovasc Imaging 2012; 5:1046-65. [DOI: 10.1016/j.jcmg.2012.07.010] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/07/2011] [Revised: 07/05/2012] [Accepted: 07/09/2012] [Indexed: 10/27/2022]
|
37
|
KYRIACOU ANDREAS, PABARI PUNAMA, WHINNETT ZACHARYI, ARRI SATPAL, WILLSON KEITH, BARUAH RESHAM, STEGEMANN BERTHOLD, MAYET JAMIL, KANAGARATNAM PRAPA, HUGHES ALUND, FRANCIS DARRELP. Fully Automatable, Reproducible, Noninvasive Simple Plethysmographic Optimization: Proof of Concept and Potential for Implantability. PACING AND CLINICAL ELECTROPHYSIOLOGY: PACE 2012; 35:948-60. [DOI: 10.1111/j.1540-8159.2012.03435.x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
|
38
|
van Deursen CJ, Strik M, Rademakers LM, van Hunnik A, Kuiper M, Wecke L, Crijns HJ, Vernooy K, Prinzen FW. Vectorcardiography as a Tool for Easy Optimization of Cardiac Resynchronization Therapy in Canine Left Bundle Branch Block Hearts. Circ Arrhythm Electrophysiol 2012; 5:544-52. [DOI: 10.1161/circep.111.966358] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Background—
In cardiac resynchronization therapy (CRT), optimization of left ventricular (LV) stimulation timing is often time consuming. We hypothesized that the QRS vector in the vectorcardiogram (VCG) reflects electric interventricular dyssynchrony, and that the QRS vector amplitude (VA
QRS
), halfway between that during left bundle branch block (LBBB) and LV pacing, reflects optimal resynchronization, and can be used for easy optimization of CRT.
Methods and Results—
In 24 canine hearts with LBBB (12 acute, 6 with heart failure, and 6 with myocardial infarction), the LV was paced over a wide range of atrioventricular (AV) delays. Surface ECGs were recorded from the limb leads, and VA
QRS
was calculated in the frontal plane. Mechanical interventricular dyssynchrony (MIVD) was determined as the time delay between upslopes of LV and right ventricular pressure curves, and systolic function was assessed as LV dP/dt
max
. VA
QRS
and MIVD were highly correlated (
r
=0.94). The VA
QRS
halfway between that during LV pacing with short AV delay and intrinsic LBBB activation accurately predicted the optimal AV delay for LV pacing (1 ms; 95% CI, –5 to 8ms). Increase in LV dP/dt
max
at the VCG predicted AV delay was only slightly lower than the highest observed ∆LV dP/dt
max
(–2.7%; 95% CI, –3.6 to –1.8%). Inability to reach the halfway value of VA
QRS
during simultaneous biventricular pacing (53% of cases) was associated with suboptimal hemodynamic response, which could be corrected by sequential pacing.
Conclusions—
The VA
QRS
reflects electric interventricular dyssynchrony and accurately predicts optimal timing of LV stimulation in canine LBBB hearts. Therefore, VCG may be useful as a reliable and easy tool for individual optimization of CRT.
Collapse
Affiliation(s)
- Caroline J.M. van Deursen
- From the Department of Physiology (C.J.M.vD., M.S., L.M.R., A.vH., M.K., L.W., F.W.P.), Department of Cardiology (H.J.G.M.C., K.V.), Cardiovascular Research Institute Maastricht, Maastricht University Medical Center, Maastricht, The Netherlands
| | - Marc Strik
- From the Department of Physiology (C.J.M.vD., M.S., L.M.R., A.vH., M.K., L.W., F.W.P.), Department of Cardiology (H.J.G.M.C., K.V.), Cardiovascular Research Institute Maastricht, Maastricht University Medical Center, Maastricht, The Netherlands
| | - Leonard M. Rademakers
- From the Department of Physiology (C.J.M.vD., M.S., L.M.R., A.vH., M.K., L.W., F.W.P.), Department of Cardiology (H.J.G.M.C., K.V.), Cardiovascular Research Institute Maastricht, Maastricht University Medical Center, Maastricht, The Netherlands
| | - Arne van Hunnik
- From the Department of Physiology (C.J.M.vD., M.S., L.M.R., A.vH., M.K., L.W., F.W.P.), Department of Cardiology (H.J.G.M.C., K.V.), Cardiovascular Research Institute Maastricht, Maastricht University Medical Center, Maastricht, The Netherlands
| | - Marion Kuiper
- From the Department of Physiology (C.J.M.vD., M.S., L.M.R., A.vH., M.K., L.W., F.W.P.), Department of Cardiology (H.J.G.M.C., K.V.), Cardiovascular Research Institute Maastricht, Maastricht University Medical Center, Maastricht, The Netherlands
| | - Liliane Wecke
- From the Department of Physiology (C.J.M.vD., M.S., L.M.R., A.vH., M.K., L.W., F.W.P.), Department of Cardiology (H.J.G.M.C., K.V.), Cardiovascular Research Institute Maastricht, Maastricht University Medical Center, Maastricht, The Netherlands
| | - Harry J.G.M Crijns
- From the Department of Physiology (C.J.M.vD., M.S., L.M.R., A.vH., M.K., L.W., F.W.P.), Department of Cardiology (H.J.G.M.C., K.V.), Cardiovascular Research Institute Maastricht, Maastricht University Medical Center, Maastricht, The Netherlands
| | - Kevin Vernooy
- From the Department of Physiology (C.J.M.vD., M.S., L.M.R., A.vH., M.K., L.W., F.W.P.), Department of Cardiology (H.J.G.M.C., K.V.), Cardiovascular Research Institute Maastricht, Maastricht University Medical Center, Maastricht, The Netherlands
| | - Frits W. Prinzen
- From the Department of Physiology (C.J.M.vD., M.S., L.M.R., A.vH., M.K., L.W., F.W.P.), Department of Cardiology (H.J.G.M.C., K.V.), Cardiovascular Research Institute Maastricht, Maastricht University Medical Center, Maastricht, The Netherlands
| |
Collapse
|
39
|
A systematic approach to designing reliable VV optimization methodology: assessment of internal validity of echocardiographic, electrocardiographic and haemodynamic optimization of cardiac resynchronization therapy. Int J Cardiol 2012; 167:954-64. [PMID: 22459364 PMCID: PMC3744806 DOI: 10.1016/j.ijcard.2012.03.086] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/08/2011] [Revised: 02/08/2012] [Accepted: 03/03/2012] [Indexed: 11/23/2022]
Abstract
Background In atrial fibrillation (AF), VV optimization of biventricular pacemakers can be examined in isolation. We used this approach to evaluate internal validity of three VV optimization methods by three criteria. Methods and results Twenty patients (16 men, age 75 ± 7) in AF were optimized, at two paced heart rates, by LVOT VTI (flow), non-invasive arterial pressure, and ECG (minimizing QRS duration). Each optimization method was evaluated for: singularity (unique peak of function), reproducibility of optimum, and biological plausibility of the distribution of optima. The reproducibility (standard deviation of the difference, SDD) of the optimal VV delay was 10 ms for pressure, versus 8 ms (p = ns) for QRS and 34 ms (p < 0.01) for flow. Singularity of optimum was 85% for pressure, 63% for ECG and 45% for flow (Chi2 = 10.9, p < 0.005). The distribution of pressure optima was biologically plausible, with 80% LV pre-excited (p = 0.007). The distributions of ECG (55% LV pre-excitation) and flow (45% LV pre-excitation) optima were no different to random (p = ns). The pressure-derived optimal VV delay is unaffected by the paced rate: SDD between slow and fast heart rate is 9 ms, no different from the reproducibility SDD at both heart rates. Conclusions Using non-invasive arterial pressure, VV delay optimization by parabolic fitting is achievable with good precision, satisfying all 3 criteria of internal validity. VV optimum is unaffected by heart rate. Neither QRS minimization nor LVOT VTI satisfy all validity criteria, and therefore seem weaker candidate modalities for VV optimization. AF, unlinking interventricular from atrioventricular delay, uniquely exposes resynchronization concepts to experimental scrutiny.
Collapse
|
40
|
Manisty CH, Al-Hussaini A, Unsworth B, Baruah R, Pabari PA, Mayet J, Hughes AD, Whinnett ZI, Francis DP. The acute effects of changes to AV delay on BP and stroke volume: potential implications for design of pacemaker optimization protocols. Circ Arrhythm Electrophysiol 2011; 5:122-30. [PMID: 22095639 DOI: 10.1161/circep.111.964205] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
BACKGROUND The AV delay optimization of biventricular pacemakers (cardiac resynchronization therapy) may maximize hemodynamic benefit but consumes specialist time to conduct echocardiographically. Noninvasive BP monitoring is a potentially automatable alternative, but it is unknown whether it gives the same information and similar precision (signal/noise ratio). Moreover, the immediate BP increment on optimization has been reported to decay away: it is unclear whether this is the result of an (undesirable) decrease in stroke volume or a (desirable) compensatory relief of peripheral vasoconstriction. METHODS AND RESULTS To discriminate between these alternative mechanisms, we measured simultaneous beat-to-beat stroke volume (flow) using Doppler echocardiography, and BP using finger photoplethysmography, during and after AV delay changes from 40 to 120 ms in 19 subjects with cardiac pacemakers. BP and stroke volume both increased immediately (P<0.001, within 1 heartbeat). BP showed a clear decline a few seconds later (average rate, -0.65 mm Hg/beat; r=0.95 [95% CI, 0.86-0.98]); in contrast, stroke volume did not decline (P=0.87). The immediate BP increment correlated strongly with the stroke volume increment (r=0.74, P<0.001). The signal/noise ratio was 3-fold better for BP than stroke volume (6.8±3.5 versus 2.3±1.4; P<0.001). CONCLUSIONS Improving AV delay immediately increases BP, but the effect begins to decay within a few seconds. Reassuringly, this is because of compensatory vasodilatation rather than reduction in cardiac function. Pacemaker optimization will never be reliable unless there is an adequate signal/noise ratio. Using BP rather than Doppler minimizes noise. The early phase (before vascular compensation) has the richest signal lode.
Collapse
Affiliation(s)
- Charlotte H Manisty
- International Centre for Circulatory Health, Imperial College London, London, UK.
| | | | | | | | | | | | | | | | | |
Collapse
|
41
|
Prinzen FW, Auricchio A. The "missing" link between acute hemodynamic effect and clinical response. J Cardiovasc Transl Res 2011; 5:188-95. [PMID: 22090350 PMCID: PMC3294218 DOI: 10.1007/s12265-011-9331-x] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/03/2011] [Accepted: 10/28/2011] [Indexed: 12/19/2022]
Abstract
The hemodynamic, mechanical and electrical effects of cardiac resynchronization therapy (CRT) occur immediate and are lasting as long as CRT is delivered. Therefore, it is reasonable to assume that acute hemodynamic effects should predict long-term outcome. However, in the literature there is more evidence against than in favour of this idea. This raises the question of what factor(s) do relate to the benefit of CRT. There is increasing evidence that dyssynchrony, presumably through the resultant abnormal local mechanical behaviour, induces extensive remodelling, comprising structure, as well as electrophysiological and contractile processes. Resynchronization has been shown to reverse these processes, even in cases of limited hemodynamic improvement. These data may indicate the need for a paradigm shift in order to achieve maximal long-term CRT response.
Collapse
Affiliation(s)
- Frits W Prinzen
- Department of Physiology, Cardiovascular Research Institute Maastricht, Maastricht, The Netherlands.
| | | |
Collapse
|
42
|
Francis DP. Precision of a Parabolic Optimum Calculated from Noisy Biological Data, and Implications for Quantitative Optimization of Biventricular Pacemakers (Cardiac Resynchronization Therapy). ACTA ACUST UNITED AC 2011. [DOI: 10.4236/am.2011.212212] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
|