Comparison of telemonitoring combined with intensive patient support with standard care in patients with chronic cardiovascular disease - a randomized clinical trial

IMPORTANCE

Healthcare concepts for chronic diseases based on tele-monitoring have become increasingly important during COVID-19 pandemic.

OBJECTIVE

To study the effectiveness of a novel integrated care concept (NICC) that combines tele-monitoring with the support of a call centre in addition to guideline therapy for patients with atrial fibrillation, heart failure, or treatment-resistant hypertension.

DESIGN

A prospective, parallel-group, open-label, randomized, controlled trial.

SETTING

Between December 2017 and August 2019 at the Rostock University Medical Center (Germany).

PARTICIPANTS

Including 960 patients with either atrial fibrillation, heart failure, or treatment-resistant hypertension.

INTERVENTIONS

Patients were randomized to either NICC (n = 478) or standard-of-care (SoC) (n = 482) in a 1:1 ratio. Patients in the NICC group received a combination of tele-monitoring and intensive follow-up and care through a call centre.

MAIN OUTCOMES AND MEASURES

Three primary endpoints were formulated: (1) composite of all-cause mortality, stroke, and myocardial infarction; (2) number of inpatient days; (3) the first plus cardiac decompensation, all measured at 12-months follow-up. Superiority was evaluated using a hierarchical multiple testing strategy for the 3 primary endpoints, where the first step is to test the second primary endpoint (hospitalization) at two-sided 5%-significance level. In case of a non-significant difference between the groups for the rate of hospitalization, the superiority of NICC over SoC is not shown.

RESULTS

The first primary endpoint occurred in 1.5% of NICC and 5.2% of SoC patients (OR: 3.3 [95%CI 1.4-8.3], p = 0.009). The number of inpatient treatment days did not differ significantly between both groups (p = 0.122). The third primary endpoint occurred in 3.6% of NICC and 8.1% of SoC patients (OR: 2.2 [95%CI 1.2-4.2], p = 0.016). Four patients died of all-cause death in the NICC and 23 in the SoC groups (OR: 4.4 [95%CI 1.6-12.6], p = 0.006). Based on the prespecified hierarchical statistical analysis protocol for multiple testing, the trial did not meet its primary outcome measure.

CONCLUSIONS AND RELEVANCE

Among patients with atrial fibrillation, heart failure, or treatment-resistant hypertension, the NICC approach was not superior over SoC, despite a significant reduction in all-cause mortality, stroke, myocardial infarction and cardiac decompensation. Trial registration ClinicalTrials.gov Identifier: NCT03317951.

Implantation of an Innovative Intracardiac Microcomputer System for Web-Based Real-Time Monitoring of Heart Failure: Usability and Patients' Attitudes

Background

Heart failure (HF) management guided by the measurement of intracardiac and pulmonary pressure values obtained through innovative permanent intracardiac microsensors has been recently proposed as a valid strategy to individualize treatment and anticipate hemodynamic destabilization. These sensors have potential to reduce patient hospitalization rates and optimize quality of life.

Objective

The aim of this study was to evaluate the usability and patients’ attitudes toward a new permanent intracardiac device implanted to remotely monitor left intra-atrial pressures (V-LAP, Vectorious Medical Technologies, Tel Aviv, Israel) in patients with chronic HF.

Methods

The V-LAP system is a miniaturized sensor implanted percutaneously across the interatrial septum. The system communicates wirelessly with a “companion device” (a wearable belt) that is placed on the patient’s chest at the time of acquisition/transmission of left heart pressure measurements. At first follow-up after implantation, the patients and health care providers were asked to fill out a questionnaire on the usability of the system, ease in performing the various required tasks (data acquisition and transmission), and overall satisfaction. Replies to the questions were mainly given using a 5-point Likert scale (1: very poor, 2: poor, 3: average, 4: good, 5: excellent). Further patient follow-ups were performed at 3, 6, and 12 months.

Results

Use and acceptance of the first 14 patients receiving the V-LAP technology worldwide and related health care providers have been analyzed to date. No periprocedural morbidity/mortality was observed. Before discharge, a tailored educational session was performed after device implantation with the patients and their health care providers. At the first follow-up, the mean score for overall comfort in technology use was 3.7 (SD 1.2) with 93% (13/14) of patients succeeding in applying and operating the system independently. For health care providers, the mean score for overall ease and comfort in use of the technology was 4.2 (SD 0.8). No significant differences were found between the patients’ and health care providers’ replies to the questionnaires. There was a general trend for higher scores in patients’ usability reports at later follow-ups, in which the score related to overall comfort with using the technology increased from 3.0 (SD 1.4) to 4.0 (SD 0.7) (P=.40) and comfort with wearing and adjusting the measuring thoracic belt increased from 2.8 (SD 1.0) to 4.2 (SD 0.4) (P=.02).

Conclusions

Despite the gravity of their HF pathology and the complexity of their comorbid profile, patients are comfortable in using the V-LAP technology and, in the majority of cases, they can correctly and consistently acquire and transmit hemodynamic data. Although the overall patient/care provider satisfaction with the V-LAP system seems to be acceptable, improvements can be achieved after ameliorating the design of the measuring tools.

Trial Registration

ClincalTrials.gov NCT03775161; https://clinicaltrials.gov/ct2/show/NCT03775161

Morphometric Characterization of Human Coronary Veins and Subvenous Epicardial Adipose Tissue-Implications for Cardiac Resynchronization Therapy Leads

Subvenous epicardial fat tissue (SEAT), which acts as an electrical insulation, and the venous diameter (VD) both constitute histomorphological challenges for optimal application and lead design in cardiac synchronization therapy (CRT). In this study, we characterized the morphology of human coronary veins to improve the technical design of future CRT systems and to optimize the application of CRT leads. We retrospectively analyzed data from cardiac computed tomography (CT) of 53 patients and did studies of 14 human hearts using the postmortem freeze section technique and micro CT. Morphometric parameters (tributary distances, offspring angles, luminal VD, and SEAT thickness) were assessed. The left posterior ventricular vein (VVSP) had a mean proximal VD of 4.0 ± 1.4 mm, the left marginal vein (VMS) of 3.2 ± 1.5 mm and the anterior interventricular vein (VIA) of 3.9 ± 1.3 mm. More distally (5 cm), VDs decreased to 2.4 ± 0.6 mm, 2.3 ± 0.7 mm, and 2.4 ± 0.6 mm, respectively. In their proximal portions (15 mm), veins possessed mean SEAT thicknesses of 3.2 ± 2.4 (VVSP), 3.4 ± 2.4 mm (VMS), and 4.2 ± 2.8 mm (VIA), respectively. More distally (20-70 mm), mean SEAT thicknesses decreased to alternating low levels of 1.3 ± 1.1 mm (VVSP), 1.7 ± 1.1 mm (VMS), and 4.3 ± 2.6 mm (VIA), respectively. In contrast to the VD, SEAT thicknesses alternated along the further distal vein course and did not display a continuous decrease. Besides the CRT responsiveness of different areas of the LV myocardium, SEAT is a relevant electrophysiological factor in CRT, potentially interfering with sensing and pacing. A sufficient VD is crucial for successful CRT lead placement. Measurements revealed a trend toward greater SEAT thickness for the VIA compared to VVSP and VMS, suggesting a superior signal-to-noise-ratio in VVSP and VMS.

Detection of arrhythmia using an implantable cardiac monitor following a cryptogenic stroke: a single-center observational study

Background

Detection of atrial fibrillation (AF) after cryptogenic stroke (CS) has therapeutic implications, but the most effective type and optimal duration of monitoring have still to be defined. This study that involved patients with CS or transient ischemic attack (TIA), all of whom carried an implantable cardiac monitor (ICM), sought to assess the incidence of AF and other arrhythmia detected using tele-monitoring or interval-based follow-up by an internal cardiologist at the university medical center of Rostock (UMR) or an external cardiologist.

Methods

The ICM implantation was performed during the inpatient stay in the neurology department, with inclusion and exclusion criteria jointly determined by the neurology and cardiology departments. Cardiologists programmed individual threshold values during ICM implantation, which were designed to instantly trigger an episode being recording and an alarm message being sent out. Outpatient care consisted of tele-monitoring of implants or interval-based follow-up care.

Results

The indication for ICM implantation was made for 102 patients, 88 of whom underwent ICM implantation, with full documentation available for these 88 study patients. Within a median observation period of 21.5 months, AF occurred in 19 patients, with a median observation time to the event of 7 months. In all cases, AF detection was followed by immediate medical intervention. Comparing patients with and without AF revealed that the median age of the AF group exceeded by 10 years that of the other patients. Stroke recurrence was recorded in five patients, with a median observation time to the event of 9 months. Comparing patients with and without stroke recurrence revealed that the median age in the stroke recurrence group tended to be higher by 14 years. No statistically significant between-group differences were found with regard to integration into tele-monitoring, nor were there any differences identified between outpatient care at the UMR or in the outpatient sector.

Conclusions

This study confirmed the feasibility of using an interdisciplinary and intersectoral therapeutic approach for monitoring CS patients with implanted ICMs. Further randomized studies are warranted to confirm these encouraging data. An open discussion concerning optimal care forms and opportunities for introducing digitizing care pathways appears warranted.

Percutaneous left atrial appendage closure for cerebrovascular accident prevention: rationale, indications, technical aspects, clinical results and future perspective

Atrial fibrillation (AF) is the most common sustained cardiac arrhythmia. The most feared complication of AF is thromboembolism. Oral anticoagulation (OAC) is the standard treatment to reduce thromboembolism occurrence in patients with AF. The rate of relevant bleeding, medical interactions and incompliance under OAC remains consistent. In this context, patients with AF at high risk for thromboembolism and with a contraindication to OAC may be considered as candidates for percutaneous left atrial appendage closure. In this review, we discuss the rationale, indications, technical aspects and clinical results of left atrial appendage closure by means of the WATCHMAN^® (Boston Scientific, MA, USA) device.

Pacing-induced cardiomyopathy in chronic right ventricular apical pacing: a midterm follow-up study

Background

Data concerning the effect of chronic right ventricular pacing in patients with normal left ventricular ejection fraction (LVEF%) are contradictory. The aim of this study is to evaluate the prevalence of pacing-induced cardiomyopathy (PICM) at midterm follow-up after permanent pacemaker implantation (PPM).

Methods

A series of 170 patients were submitted to PPM within our facility. Inclusion criteria were the absence of structural heart disease and a preserved LVEF% (> 45%) at the time of PPM. A midterm clinical and echocardiographic follow-up was performed, and data were collected and analyzed retrospectively. PICM was defined as follow-up LVEF ≤ 45%, dyskinesia during RV pacing, and the absence of other known causes of cardiomyopathy.

Results

At a median echocardiographic follow-up of 24.5 months (IQR 10.0–43.0 months), the overall mean LVEF% decreased from a preimplantation value of 66.7% (± 8.6%) to 63.2% (± 10.6%) (p < 0.0001). PICM occurred in 11 patients (6.5%). Patients developing PICM had a significantly lower preimplantation LVEF% (58.4 ± 8.0% vs. 67.3 ± 8.4%; p = 0.005), a trend for higher right ventricular pacing time rate (0.7 ± 0.3 vs. 0.5 ± 0.4; p = 0.1), a significantly lower rate of PPM indication for sick sinus syndrome (SSS) (18.2% vs. 61.0%; p = 0.009), and significantly higher rate of second-grade cardiac conduction block (36.4% vs. 11.3%; p = 0.03). At multivariate logistic regression, only preimplantation LVEF% (OR = 0.88; CI 0.80–0.96; p = 0.006) and the presence of SSS (OR = 0.1; CI 0.03–0.9; p = 0.04) were independently related (inverse relationship) to follow-up PICM.

Conclusions

In this selected PPM patient cohort with preserved LVEF%, the rate of PICM at midterm follow-up is relatively low, but its occurrence seems to be related to baseline LVEF% and PPM indication category.

Deactivation of cardiovascular implantable electronic devices in patients nearing end of life : Reality or only recommendation?

BACKGROUND

Current guidelines recommend considering deactivation of cardiac implantable electronic devices (CIEDs) in patients nearing death. We evaluated the implementation of this recommendation in unselected deceased individuals with CIEDs.

METHODS

Over a 7-month period in 2016, all deceased persons taken to the Rostock crematorium were prospectively screened for CIEDs and these were interrogated in situ. Pacing rate, pacing mode, and lead output were documented as well as patient data including location and time of death. In implantable cardioverter-defibrillators (ICDs), tachycardia therapy adjustment and occurrence of shocks 24 h prior to death were also recorded.

RESULTS

We examined 2297 subjects, of whom 154 (6.7%) had CIEDs. Of these subjects, 125 (100%) pacemakers (PMs) and 27 (96.4%) ICDs were eligible for analysis. Death in persons with ICDs occurred most frequently in hospital (55.6%), while this was less frequently the case for individuals with PMs (43.2%). Furthermore, 33.3% of subjects with ICDs and 18.5% with PMs died in palliative care units (PCU). Shock therapies were switched off in three (60%) individuals with ICDs who died in the PCU, whereas antibradycardia therapy was not withdrawn in any PM patient in the PCU. Therapy withdrawal occurred in two patients with PMs (1.3%) who died in hospital. Patients with PMs had high ventricular pacing rates at the last interrogation (69 ± 36.0%) and often suffered atrioventricular block (39.2%). Six (25%) of the 24 active ICDs presented shocks near the time of death.

CONCLUSION

Many CIED patients died in hospital; nonetheless, in practice, CIED deactivation near death is rarely performed and might be less feasible in subjects with PMs. However, there is still a need to consider deactivation, especially in individuals with ICDs, as one fourth of them received at least one shock within 24 h prior to death.

Individual programming of current multiprogrammable pacemakers : Still unsatisfactory?

BACKGROUND

Pacemaker (PM) technology has developed tremendously in recent decades. We evaluated the extent of individual programming in current PMs.

METHODS

Over a 7-month period in 2016, all deceased persons taken to the Rostock crematorium were prospectively screened for cardiac implantable electronic devices (CIEDs) and these were interrogated in situ. Programming of patient data, leads, and study parameters including mode, lower rate, upper tracking or sensor rate (UTSR), ventricular refractory time, sleeping function, hysteresis, and PM-mediated tachycardia intervention were analyzed and compared with delivery settings. Alterations in atrial/ventricular capture management and atrial/ventricular sensing assurance as well as changes in sensitivity and lead output were evaluated.

RESULTS

We examined 2297 subjects, of whom 154 (6.7%) had CIEDs, with 125 (81.2%) being PMs. Finally, 72 (57.6%) PMs were eligible for analysis with an operation time of 31.0 ± 27.0 months. We excluded 28 (18.2%) implantable cardioverter defibrillators (ICDs), 51 (41%) PMs presenting elective replacement indicator (ERI), two (1.6%) PMs with programming to insufficient function prior to death, and the left ventricle parameter of one (1.4%) cardiac resynchronization therapy pacemaker (CRT-P); further one CIED (0.6%) was not contactable. PMs offered in mean 75.2% of study parameters thereof 88.0% were to adjust manually, whereof 49.3% stayed unchanged to delivery mode. Lead output, UTSR, lower rate, and mode were the most frequently changed parameters (>85.7%, 65.3%, 54.2%, and 52.8%, respectively) compared with unmodified ventricular refractory time and hysteresis (91.7% and. 85.4%, respectively); 2.8% of PMs had out-of-the-box settings. The most frequent personalized data were last (88.9%) and first name (73.6%), while atrial and ventricular serial lead numbers were rarely entered (18.2% and 23.4%, respectively).

CONCLUSION

The programming possibilities of PMs have advanced greatly. Nonetheless, improvements in individual PM programming are still needed as demonstrated by the findings in this study, e.g., PMs with manufacturer settings and lack of individual data.

Transcatheter aortic valve implantation with a mechanically expandable prosthesis: a learning experience for permanent pacemaker implantation rate reduction

Background

Permanent pacemaker implantation (PPMI) after transcatheter aortic valve implantation (TAVI) remains an issue open for criticism. Aim of this study is to investigate a strategy to reduce PPMI rate after TAVI in general and more specifically after implantation of the LOTUS^® prosthesis.

Methods

Through our learning curve, we have developed a structured protocol to reduce PPMI rate. The protocol includes: shallow implantation depth within the native annulus, strict adherence to the international guidelines for PPMI, PPMI not earlier than 5 days after TAVI, and intravenous chronotropic and steroidal treatment (orciprenaline 0.6–1.7 mg/h i.v. and dexamethasone 25 mg/day i.v. for a maximum of 5 days) in case of acute onset of intraventricular and/or atrio-ventricular conduction disturbances after TAVI.

Results

The first 35 patients (group A) were managed as per routine in our early stage experience with the LOTUS valve. The PPMI reduction protocol was applied in the second phase on the last 31 patients (group B). The PPMI rate was reduced from 34.3% (12/35) to 9.7% (3/31) (p = 0.02). At logistic regression analysis being treated in the second phase of our experience (group B) had a protective effect against PPMI (p = 0.05; OR = 0.1; CI = 0.01–1.0). Prosthesis implantation depth was directly related to PPMI (p = 0.005; OR = 2.0; CI = 1.2–3.2). Receiver operating characteristic curve analysis confirmed that a LOTUS implantation depth > 4.8 mm was the cut-off to predict PPMI (AUC = 0.8; p = 0.003; CI = 0.6–0.9) with maximal sensitivity (78.6%) and specificity (73.2%).

Conclusions

PPMI rate after LOTUS can be reduced with experience by applying specific clinical and operative strategies.

Activation of remote monitoring for cardiac implantable electronic devices: small dog for tall weeds

BACKGROUND

Remote monitoring (RM) of cardiac implantable electronic devices (CIEDs) has been popularized as a precious patients' management tool. We have investigated RM within the premises of a multicenter, prospective, real-world registry, i.e., the German Device II.

METHODS

We have focused on: (1) CIEDs with RM capabilities implantation rate and (2) actual rate of RM features activation.

RESULTS

A cohort of 1223 CIEDs patients were treated from 04/11 to 02/14. Of these, 720 (58.8%) were implanted with RM-capable devices and were presenting significantly more often a clinical diagnosis of dilatative cardiomyopathy and an indication for cardiac resynchronization. At discharge, the RM feature was activated in only 12.6% (91/720) of the total number of patients implanted with RM-capable CIEDs. After adjusting for implanting center, there was no significant correlation between any of the patient clinical characteristics and RM activation. One-year estimated mortality was 9.0% in patients with activated RM, 5.6% in those with not activated RM, and 7.7% in those without RM capability (p = 0.3). The RM feature was still activated in 13.8% of the patients surviving at follow-up. Patients undergoing RM had a trend for higher re-hospitalization rate and less visits in the device outpatient clinic.

CONCLUSIONS

Although RM in CIEDs may be a clinically valuable technological armamentarium, its activation does not reflect patients' clinical profile. In fact, RM is often not activated, most probably because it is still recognized as a source of increased workload in a reality where reimbursement plans for dedicated human resources are not yet optimized.

Percutaneous treatment of adult isthmic aortic coarctation: acute and long-term clinical and imaging outcome with a self-expandable uncovered nitinol stent

BACKGROUND

To present perioperative and long-term results of percutaneous treatment of adult isthmic coarctation of the aorta by means of a self-expandable closed-web uncovered nitinol stent (Sinus-XL, Optimed, Esslingen, Germany).

METHODS AND RESULTS

Preoperative, perioperative, and long-term clinical and computed tomographic angiography data were collected and analyzed prospectively. A total of 52 consecutive patients were treated with the Sinus-XL stent. Mean age was 36.6 (21-67) years, peak invasive trans-coarctation of the aorta gradient was 54.7 ± 9.9 mm Hg, and upper body hypertension unresponsive to medical treatment was present in all patients. Mean stent diameter and length were 24.2 mm (22-28 mm) and 70.4 mm (40-80 mm), respectively. Eight patients (15.4%) required coarctation of the aorta predilatation. All patients underwent poststent dilatation with a noncompliant balloon. Postoperative peak gradient (3.3 ± 2.5 mm Hg) was reduced significantly (P < 0.001) and minimal aortic diameter was increased significantly (4.6 ± 1.9 versus 18.6 ± 2.5 mm; P < 0.001). All patients were discharged home (mean hospitalization, 3.5 days). At follow-up (47.6 months; 12-84), 1 (1.9%) noncardiovascular mortality was reported. Aortic computed tomography confirmed the absence of stent collapse and secondary migration and documented stability in aortic diameter (18.3 ± 2.7 mm). Thirty patients (57.7%) were completely weaned-off antihypertensive medications and their use dropped from 2.6 to 0.9 drugs/patient (P < 0.001). Ankle-brachial pressure index increased from 0.75 to 0.98 (P < 0.001).

CONCLUSIONS

Adult coarctation of the aorta treatment by means of a self-expandable uncovered stent is safe and durable. The peculiar stent design maintains adequate localized radial strength over time with minimal trauma on the adjacent aortic wall and negligible device-related complications. Blood pressure control optimization is immediate and persistent even at long-term follow-up.

Endovascular treatment of acquired atheromatous aortic arch coarctation

Acquired aortic coarctation is a rare condition. Its treatment using a percutaneous approach can be challenging, especially when severe calcifications and concomitant aneurysmal disease are present. We report a patient with symptomatic thoracic aorta acquired coarctation and aneurysm that was successfully treated using endovascular technique. After left subclavian artery transposition, a self-expanding endograft was implanted percutaneously, with complete abolishment of the transaortic gradient. Follow-up evaluation at 12 months revealed perfect position of the endograft, persistent reduction of the coarctation, and exclusion of the concomitant aneurysm. A noninvasive pressure reading demonstrated significant systemic blood pressure reduction, with no change in antihypertensive medications.

Complicated type B aortic dissection should not be treated with uncovered stents: a lesson not yet learned

Whenever some basic rules for endovascular aortic repair of type B aortic dissection are not followed, iatrogenic complications may develop. A 64-year-old gentleman was referred to our institution for revision of previous treatment of complex type B aortic dissection with 2 bare stents. At 3 months, the most proximal aortic bare stent had entered, via the proximal tear, the false lumen. Aortic expansion and dynamic obstruction at the level of the renal arteries had also developed. In a first step, we removed the proximal aortic bare stent surgically. Few days later, 2 covered endografts were implanted into the true lumen of the thoracic aorta with clinical success. The rationale for using endovascular treatment in patients with complicated type B aortic dissection is coverage of the entry tear with covered nonoversized endografts. Negative results are achieved whenever these very simple rules are not strictly followed.

Percutaneous mitral repair with the MitraClip system in patients with mild-to-moderate and severe heart failure: a single-centre experience

AIMS

Edge-to-edge repair of mitral regurgitation (MR) with the MitraClip(®) (MC) system is increasingly applied in advanced heart failure. Our objective was to compare outcomes in patients with mild-to-moderate and severe systolic heart failure.

METHODS AND RESULTS

Between February 2010 and July 2012, 121 patients with MR of at least grade 3+ and a mean EuroSCORE II of 10.6% underwent MC implantation. Thirty-nine had a left ventricular ejection fraction (LVEF) of ≤30% (group A) and 82 of >30% (group B). Procedural success was comparable in both groups (100% vs. 95.2%) with multiple (>2) clip implantation in 34% and 25% of patients, respectively. At 12 months, absolute reduction in MR grade (2.3 vs. 2.2) and relative reduction in mitral valve orifice area (48% vs. 42%) were also comparable. New York Heart Association class had improved independent from baseline LVEF (P < 0.001). In-hospital mortality was low in both groups (2.6% vs. 2.4%), but there was a strong trend for higher 12-month mortality in group A (34% vs. 18%, P = 0.05) with no significant difference in the overall rate of major adverse cerebrovascular and cardiac events (36.8% vs. 28.9%, P = 0.38). On multivariate analysis, MR grade after repair was the strongest predictor of mortality (OR 2.121, 95% CI 1.095-4.109), whereas systolic impairment was no independent predictor.

CONCLUSIONS

Percutaneous mitral valve repair led to comparable symptomatic improvement in patients with mild-to-moderately or severely reduced LV function. LV-EF < 30% was not an independent predictor of short-term mortality, which was mainly governed by residual MR after repair.

How should I treat a challenging case of MitraClip implantation?

BACKGROUND

A 71-year-old woman affected by idiopathic dilated cardiomyopathy with normal coronary arteries and permanent atrial fibrillation was found to have severe mitral regurgitation at transthoracic echocardiography (TTE), due to annular dilatation and restricted motion of the posterior leaflet. Because of poor quality of life, high functional class (NYHA Class III) and the high risk of surgery, the patient agreed to undergo the implantation of a MitraClip device. During the procedure, the transoesophageal echocardiographic (TEE) images were of a poor quality since the view of the mitral valve in the mid-oesophageal and transgastric projections did not accurately show the valve leaflets and the convergence area of the regurgitation at colour Doppler, which is indispensable for the correct positioning of the clip.

INVESTIGATION

Physical examination, transthoracic echocardiography, transoesophageal echocardiography.

DIAGNOSIS

Severe mitral regurgitation suitable for MitraClip implantation.

MANAGEMENT

Transthoracic, and not transoesophageal, echocardiography approach during MitraClip procedure.

Mitral valve repair using multiple MitraClips®: a dobutamine stress echocardiography evaluation

AIMS

The haemodynamic effect of mitral valve (MV) repair using multiple MitraClips® (MC) has not been investigated. The aim of the study was to evaluate the stress performance of MV repair with MC.

METHODS AND RESULTS

Twenty consecutive patients (77±7 years, 13 men [65%]) after implantation of >2 MitraClips® were subsequently evaluated with dobutamine stress echocardiography (DSE). After MC implantation, mean transmitral pressure gradient (TPG) (3.3±0.8 mmHg vs. 4.0±0.6 mmHg; p<0.001) and mitral valve orifice area (2.9±0.3 cm2 vs. 3.9±0.4 cm2; p<0.001) were significantly increased during DSE showing a physiological behaviour effect of the MV. LVEF (41±18% vs. 46±21%; p<0.001) and systolic pulmonary artery pressure (42±11 mmHg vs. 44±12 mmHg; p=0.014) increased significantly. The degree of MR was stable during stress (p=0.68). At linear regression, only baseline peak TPG was related to stress mean TPG (p<0.001; Beta 0.816; 95% CI: 0.368-0.918).

CONCLUSIONS

MV repair using MitraClips® should be performed with the aim of maximal reduction of MR degree. MV repair using MC may not lead to pathological degrees of MV stenosis. Although the TPG is significantly increased during stress, it never reaches pathological levels and is always accompanied by a significant increase in MVOA. The degree of residual MR remains unchanged during maximal pharmacological stress.

Enhanced mobilization of the bone marrow-derived circulating progenitor cells by intracoronary freshly isolated bone marrow cells transplantation in patients with acute myocardial infarction

Autologous bone marrow cell transplantation (BMCs-Tx) is a promising novel option for treatment of cardiovascular disease. We analysed in a randomized controlled study the influence of the intracoronary autologous freshly isolated BMCs-Tx on the mobilization of bone marrow–derived circulating progenitor cells (BM-CPCs) in patients with acute myocardial infarction (AMI). Sixty-two patients with AMI were randomized to either freshly isolated BMCs-Tx or to a control group without cell therapy. Peripheral blood (PB) concentrations of CD34/45⁺- and CD133/45⁺-circulating progenitor cells were measured by flow cytometry in 42 AMI patients with cell therapy as well as in 20 AMI patients without cell therapy as a control group on days 1, 3, 5, 7, 8 and 3, 6 as well as 12 months after AMI. Global ejection fraction (EF) and the size of infarct area were determined by left ventriculography. We observed in patients with freshly isolated BMCs-Tx at 3 and 12 months follow up a significant reduction of infarct size and increase of global EF as well as infarct wall movement velocity. The mobilization of CD34/45⁺ and CD133/45⁺ BM-CPCs significantly increased with a peak on day 7 as compared to baseline after AMI in both groups (CD34/45⁺: P < 0.001, CD133/45⁺: P < 0.001). Moreover, this significant mobilization of BM-CPCs existed 3, 6 and 12 months after cell therapy compared to day 1 after AMI. In control group, there were no significant differences of CD34/45⁺ and CD133/45⁺ BM-CPCs mobilization between day 1 and 3, 6 and 12 months after AMI. Intracoronary transplantation of autologous freshly isolated BMCs by use of point of care system in patients with AMI may enhance and prolong the mobilization of CD34/45⁺ and CD133/45⁺ BM-CPCs in PB and this might increase the regenerative potency after AMI.

Predictive factors for pacemaker requirement after transcatheter aortic valve implantation

Background

Transcatheter aortic valve implantation (TAVI) has been established as a treatment option for inoperable patients with symptomatic aortic valve stenosis. However, patients suffer frequently from conduction disturbances after TAVI.

Methods

Baseline, procedural as well as surface and intracardiac ECG parameters were evaluated for patients treated with TAVI and a comparison between patients requiring pacemaker with those not suffering from relevant conduction disorders were done.

Results

TAVI was successfully in all patients (n=45). Baseline surface and intracardiac ECG recording revealed longer PQ (197.1±51.2 msec versus 154.1±32.1 msec; p<0.001), longer AH (153.6±43.4 msec versus 116.1±31.2 msec; p<0.001) and HV interval (81.7±17.8 msec versus 56.8±8.5 msec; p<0.001) in patients with need for a pacemaker (n=23) versus control group (n=22); furthermore, 7-day follow-up analysis showed a higher prevalence of new left bundle branch block (LBBB) (87.0% versus 31.9%; p<0.001). Multivariate analysis revealed that only new LBBB, QRS duration >120 msec and a PQ interval >200 msec immediately (within 60 minutes) after implantation of the aortic valve were predictors for high-grade (type II second-degree and third-degree) AV block. Other clinical parameters as well as baseline electrocardiographic parameters had no impact on critical conduction delay.

Conclusion

Cardiac conduction disturbances are common after TAVI. The need for pacing after TAVI is predictable by surface ECG evaluation immediately (within 60 minutes) after the procedure.

Morbidity and mortality of nonagenarians undergoing CoreValve implantation

Background

Nonagenarians are mostly denied from different therapeutic strategies due to high comorbidity index and risk-benefit calculation. We present the results of nonagenarians with high comorbidity index not eligible for conventional aortic valve surgery undergoing transcatheter aortic valve implantation (TAVI) with the CoreValve system.

Methods

Our retrospective analysis include baseline parameters, procedural characteristics, morbidity, mortality as well as twelve-lead surface ECG and echocardiographic parameters which were revealed preinterventionally, at hospital discharge and at 30-day follow-up. Clinical follow-up was performed 6 months after TAVI.

Results

Out of 158 patients 11 nonagenarians with a mean age of 92.6 ± 1.3 years suffering from severe aortic valve stenosis and elevated comorbidity index (logistic EuroSCORE of 32.0 ± 9.5%, STS score 25.3 ± 9.7%) underwent TAVI between January 2008 and January 2011 using the third-generation percutaneous self-expanding CoreValve prosthesis. Baseline transthoracic echocardiography reported a mean aortic valve area (AVA) of 0.6 ± 0.2 cm² with a mean and peak pressure gradient of 60.2 ± 13.1mmHg and 91.0 ± 27.4mmHg, respectively. The 30-day follow up all cause and cardiovascular mortality was 27.3% and 9.1%, respectively. One major stroke (9.1%), 2 pulmonary embolisms (18.2%), 1 periprocedural (9.1%) and 1 (9.1%) spontaneous myocardial infarction occured. Life-threatening or disabling bleeding occurred in 2 cases (18.2%), and minor bleeding in 7 cases (63.6%). Mean severity of heart failure according to NYHA functional class improved from 3.2 ± 0.8 to 1.36 ± 0.5 while mean AVA increased from 0.6 ± 0.2cm² to 1.8 ± 0.2cm². At 6-months follow-up 8 patients (72.7%) were alive without any additional myocardial infarction, pulmonary embolism, bleeding, or stroke as compared to 30-day follow-up.

Conclusion

Our case series demonstrate that even with elevated comorbidity index, clinical endpoints and valve-associated results are relatively favorable in nonagenarians treated with CoreValve.

Iyengar yoga increases cardiac parasympathetic nervous modulation among healthy yoga practitioners

Relaxation techniques are established in managing of cardiac patients during rehabilitation aiming to reduce future adverse cardiac events. It has been hypothesized that relaxation-training programs may significantly improve cardiac autonomic nervous tone. However, this has not been proven for all available relaxation techniques. We tested this assumption by investigating cardiac vagal modulation during yoga.We examined 11 healthy yoga practitioners (7 women and 4 men, mean age: 43 ± 11; range: 26–58 years). Each individual was subjected to training units of 90 min once a week over five successive weeks. During two sessions, they practiced a yoga program developed for cardiac patients by B.K.S. Iyengar. On three sessions, they practiced a placebo program of relaxation. On each training day they underwent ambulatory 24 h Holter monitoring. The group of yoga practitioners was compared to a matched group of healthy individuals not practicing any relaxation techniques. Parameters of heart rate variability (HRV) were determined hourly by a blinded observer. Mean RR interval (interval between two R-waves of the ECG) was significantly higher during the time of yoga intervention compared to placebo and to control (P < 0.001 for both). The increase in HRV parameters was significantly higher during yoga exercise than during placebo and control especially for the parameters associated with vagal tone, i.e. mean standard deviation of NN (Normal Beat to Normal Beat of the ECG) intervals for all 5-min intervals (SDNNi, P < 0.001 for both) and root mean square successive difference (rMSSD, P < 0.01 for both). In conclusion, relaxation by yoga training is associated with a significant increase of cardiac vagal modulation. Since this method is easy to apply with no side effects, it could be a suitable intervention in cardiac rehabilitation programs.

Correlation between the functional impairment of bone marrow-derived circulating progenitor cells and the extend of coronary artery disease

Background

Bone marrow-derived circulating progenitor cells (BM-CPCs) in patients with coronary heart disease are impaired with respect to number and functional activity. However, the relation between the functional activity of BM-CPCs and the number of diseased coronary arteries is yet not known. We analyzed the influence of the number of diseased coronary arteries on the functional activity of BM-CPCs in peripheral blood (PB) in patients with ischemic heart disease (IHD).

Methods

The functional activity of BM-CPCs was measured by migration assay and colony forming unit in 120 patients with coronary 1 vessel (IHD1, n = 40), coronary 2 vessel (IHD2, n = 40), coronary 3 vessel disease (IHD3, n = 40) and in a control group of healthy subjects (n = 40). There was no significant difference of the total number of cardiovascular risk factors between IHD groups, beside diabetes mellitus (DM), which was significantly higher in IHD3 group compared to IHD2 and IHD1.

Results

The colony-forming capacity (CFU-E: p < 0.001, CFU-GM: p < 0.001) and migratory response to stromal cell-derived factor 1 (SDF-1: p < 0.001) as well as vascular endothelial growth factor (VEGF: p < 0001) of BM-CPCs were reduced in the group of patients with IHD compared to control group. The functional activity of BM-CPCs was significantly impaired in patients with IHD3 as compared to IHD1 (VEGF: p < 0.01, SDF-1: p < 0.001; CFU-E: p < 0.001, CFU-GM: p < 0.001) and to IHD2 (VEGF: p = 0.003, SDF-1: p = 0.003; CFU-E: p = 0.001, CFU-GM: p = 0.001). No significant differences were observed in functional activity of BM-CPCs between patients with IHD2 and IHD1 (VEGF: p = 0.8, SDF-1: p = 0.9; CFU-E: p = 0.1, CFU-GM: p = 0.1). Interestingly, the levels of haemoglobin AIc (HbAIc) correlated inversely with the functional activity of BM-CPCs (VEGF: p < 0.001, r = −0.8 SDF-1: p < 0.001, r = −0.8; CFU-E: p = 0.001, r = −0.7, CFU-GM: p = 0.001, r = −0.6) in IHD patients with DM.

Conclusions

The functional activity of BM-CPCs in PB is impaired in patients with IHD. This impairment increases with the number of diseased coronary arteries. Moreover, the regenerative capacity of BM-CPCs in ischemic tissue further declines in IHD patients with DM. Furthermore, monitoring the level of BM-CPCs in PB may provide new insights in patients with IHD.

Intra coronary freshly isolated bone marrow cells transplantation improve cardiac function in patients with ischemic heart disease

Background

Autologous bone marrow cell transplantation (BMCs-Tx) is a promising novel option for treatment of cardiovascular disease. In this study we analyzed whether intracoronary autologous freshly isolated BMCs-Tx have beneficial effects on cardiac function in patients with ischemic heart disease (IHD).

Results

In this prospective nonrandomized study we treated 12 patients with IHD by freshly isolated BMCs-Tx by use of point of care system and compared them with a representative 12 control group without cell therapy. Global ejection fraction (EF) and infarct size area were determined by left ventriculography.

Intracoronary transplantation of autologous freshly isolated BMCs led to a significant reduction of infarct size (p < 0.001) and an increase of global EF (p = 0.003) as well as infarct wall movement velocity (p < 0.001) after 6 months follow-up compared to control group. In control group there were no significant differences of global EF, infarct size and infarct wall movement velocity between baseline and 6 months after coronary angiography. Furthermore, we found significant decrease in New York Heart Association (NYHA) as well as significant decrease of B-type natriuretic peptide (BNP) level 6 months after intracoronary cell therapy (p < 0.001), whereas there were no significant differences in control group 6 months after coronary angiography.

Conclusions

These results demonstrate that intracoronary transplantation of autologous freshly isolated BMCs by use of point of care system is safe and may lead to improvement of cardiac function in patients with IHD.

Trial registration

Registration number: ISRCTN54510226

Surface and intracardiac ECG for discriminating conduction disorders after CoreValve implantation

Background

Transcatheter aortic valve implantation (TAVI) has been developed to minimize operative morbidity and mortality in high-risk symptomatic patients unfit for open surgery. With the proximity of the aortic valve annulus to the conduction system there is, however, an unknown risk of conduction disturbances necessitating monitoring and often cardiac pacing.

Materials and methods

We enrolled 50 consecutive patients from January 2007 to 2008 in our prospective evaluation of conduction disturbances measured by surface and intracardiac ECG recordings. Baseline parameters, procedural characteristics as well as twelve-lead surface ECG and intracardiac conduction times were revealed pre-interventionally, after TAVI and at 7-day follow-up.

Results

TAVI was performed successfully in all patients. During 7 days of follow-up the rate for first-degree AV block raised from 14% at baseline to 44% at day 7 (p < 0.001), while rates for type II second- and third-degree were 0 versus 8% (p < 0.001) and 0 versus 12% (p < 0.001), respectively. Similarly, the prevalence of new left bundle branch block (LBBB) rose from 2 to 54% (p < 0.001). Intracardiac measurements revealed a prolongation of both AH and HV interval from 123.7 ± 41.6 to 136.6 ± 40.5 ms (p < 0.001) and from 54.8 ± 11.7 to 71.4 ± 20.0 ms (p < 0.001), respectively. Pacemaker implantation at a mean follow-up of 4.8 ± 1.2 days was subsequently performed in 23 patients (46%) due to complete AV block (12%) and type II second-degree AV block (8%) while another 13 patients (26%) received a pacemaker for the combination of new LBBB with marked HV prolongation. The high rate of first-degree AV block was primarily driven by an increase in HV interval.

Conclusion

Cardiac conduction disturbances were common in the early experience with CoreValve implantation necessitating close surveillance for at least 1 week.

Relation between the frequency of CD34⁺ bone marrow derived circulating progenitor cells and the number of diseased coronary arteries in patients with myocardial ischemia and diabetes

BACKGROUND

Bone marrow-derived circulating progenitor cells (BM-CPCs) in patients with coronary heart disease are impaired with respect to number and mobilization. However, it is unknown whether the mobilization of BM-CPCs depends on the number of diseased coronary arteries. Therefore, in our study, we analysed the correlation between the diseased coronary arteries and the frequency of CD34/45+ BM-CPCs in peripheral blood (PB) in patients with ischemic heart disease (IHD).

METHODS

The frequency of CD34/45+ BM-CPCs was measured by flow cytometry in 120 patients with coronary 1 vessel (IHD1, n = 40), coronary 2 vessel (IHD2, n = 40), coronary 3 vessel disease (IHD3, n = 40) and in a control group of healthy subjects (n = 40). There was no significant difference of the total number of cardiovascular risk factors between IHD groups, beside diabetes mellitus (DM), which was significantly higher in IHD3 group compared to IHD2 and IHD1 groups.

RESULTS

The frequency of CD34/45+ BM-CPCs was significantly reduced in patients with IHD compared to the control group (CD34/45+; p < 0.001). The frequency of BM-CPCs was impaired in patients with IHD3 compared to IHD1 (CD34/45+; p < 0.001) and to IHD2 (CD34/45+; p = 0.001). But there was no significant difference in frequency of BM-CPCs between the patients with IHD2 and IHD1 (CD34/45+; p = 0.28). In a subgroup we observed a significant negative correlation between levels of hemoglobin AIc (HbAIc) and the frequency of BM-CPCs (CD34/45+; p < 0.001, r = -0.8).

CONCLUSIONS

The frequency of CD34/45+ BM-CPCs in PB is impaired in patients with IHD. This impairment may augment with an increased number of diseased coronary arteries. Moreover, the frequency of CD34/45+ BM-CPCs in ischemic tissue is further impaired by diabetes in patients with IHD.

Improved functional activity of bone marrow derived circulating progenitor cells after intra coronary freshly isolated bone marrow cells transplantation in patients with ischemic heart disease

Objectives

There is growing evidence that intracoronary autologous bone marrow cells transplantation (BMCs-Tx) in patients with chronic myocardial infarction beneficially affects postinfarction remodelling. In this randomized controlled study we analyzed the influence of intracoronary autologous freshly isolated bone marrow cells transplantation by use of point of care system on cardiac function and on the functional activity of bone marrow derived circulating progenitor cells (BM-CPCs) in patients with ischemic heart disease (IHD).

Methods

56 patients with IHD were randomized to either received freshly isolated BMC-Tx or a control group that did not receive cell therapy. The functional activity of BM-CPCs in peripheral blood (PB) was measured by migration assay and colony forming unit assay pre- and 3, 6 as well as 12 months after procedure. Global ejection fraction (EF) and infarct size area were determined by left ventriculography.

Results

Intracoronary transplantation of autologous freshly isolated BMCs led to a significant reduction of infarct size and an increase of global EF as well as infarct wall movement velocity after 3 and 12 months follow-up compared to control group. The colony-forming capacity of BM-CPCs significantly increased 3, 6 and 12 months after cell therapy compared to pre BMCs-Tx and control group (CFU-E: p < 0.001, CFU-GM: p < 0.001). Likewise, we found significant increase of migratory response to stromal cell-derived factor 1 (SDF-1) and vascular endothelial growth factor (VEGF) after cell therapy compared to pre BMCs-Tx (SDF-1: p < 0.001, VEGF: p < 0.001) and to control (SDF-1: p < 0.001, VEGF: p < 0.001). There was no significant difference of migratory- and colony forming capacity between pre- and 3, 6, 12 months after coronary angiography in control group without cell therapy.

Conclusions

Intracoronary transplantation of autologous freshly isolated BMCs by use of point of care system may lead to improvement of BM-CPCs functional activity in peripheral blood, which might increase the regenerative potency in patients with IHD.

Very late coronary aneurysm formation with subsequent stent thrombosis secondary to drug-eluting stent

Drug-eluting stents have changed the practice in interventional cardiology. With the widespread use of these stents important safety concerns regarding stent thrombosis and formation of coronary artery aneurysm have been expressed. While the majority of attention was focused on stent thrombosis, the formation of coronary aneurysm was only described in anecdotal reports. We report on a patient who suffered from very late stent thrombosis in association with coronary artery aneurysm formation secondary to drug-eluting stent but not to bare-metal stent.

Impaired mobilization of CD133(+) bone marrow-derived circulating progenitor cells with an increased number of diseased coronary arteries in ischemic heart disease patients with diabetes

BACKGROUND

The influence of the number of diseased coronary arteries on the mobilization of CD133/45(+) bone marrow-derived circulating progenitor cells (BM-CPCs) in peripheral blood (PB) in patients with ischemic heart disease (IHD) was analyzed.

METHODS AND RESULTS

Mobilization of CD133/45(+) BM-CPCs by flow cytometry was measured in 120 patients with coronary 1 vessel (IHD1, n=40), coronary 2 vessel (IHD2, n=40), and coronary 3 vessel disease (IHD3, n=40), and in a control group (n=40). The mobilization of CD133/45(+) BM-CPCs was significantly reduced in patients with IHD compared to the control group (P<0.001). The mobilization of CD133/45(+) BM-CPCs was impaired in patients with IHD3 compared to IHD1 (P<0.001) and to IHD2 (P<0.001). But there was no significant difference in mobilization of CD133/45(+) BM-CPCs between the patients with IHD2 and IHD1 (P=0.35). Moreover, we found significantly reduced CD133/45(+) cell mobilization in patients with a high SYNTAX-Score (SS) compared to a low SS (P<0.001) and an intermediate SS (P<0.001). In subgroup analyzes, we observed a significantly negative correlation between levels of hemoglobin A(1c) and the mobilization of CD133/45(+) BM-CPCs (P=0.001, r=-0.6).

CONCLUSIONS

The mobilization of CD133/45(+) BM-CPCs in PB is impaired in patients with IHD. This impairment might augment with increased number of diseased coronary arteries. Moreover, mobilization of CD133/45(+) BM-CPCs in ischemic tissue is further impaired by diabetes in patients with IHD.

Improvement of cardiac function by intracoronary freshly isolated bone marrow cells transplantation in patients with acute myocardial infarction

BACKGROUND

We analyzed in the present study the influence of intracoronary autologous freshly isolated bone marrow cells transplantation (BMCs-Tx) on cardiac function in patients with acute myocardial infarction (AMI).

METHODS AND RESULTS

The 32 patients with AMI were enrolled in this prospective nonrandomized study to either freshly isolated BMC-Tx or to a control group without cell therapy. Global left ventricular ejection fraction (LVEF) and the size of infarct area were determined by left ventriculography. We observed in patients with autologous freshly isolated BMCs-Tx at 6 months follow up a significant reduction of infarct size as compared to control group. Moreover, we found a significant increase of LVEF as well as infarct wall movement velocity at 6 months follow up in cell therapy group as compared to control group. In the control group there was no significant difference of LVEF, infarct size and infarct wall movement velocity between baseline and 6 months after AMI.

CONCLUSIONS

These results demonstrate for the first time that intracoronary transplantation of autologous freshly isolated BMCs by use of a point of care system is safe, and may lead to improvement of cardiac function in patients with AMI.

Improved mobilization of the CD34(+) and CD133(+) bone marrow-derived circulating progenitor cells by freshly isolated intracoronary bone marrow cell transplantation in patients with ischemic heart disease

Cell therapy is a promising novel option for treatment of cardiovascular disease. Because the role of bone marrow-derived circulating progenitor cells (BM-CPCs) after cell therapy is less clear, we analyzed in this randomized, controlled study the influence of intracoronary autologous freshly isolated bone marrow cell transplantation (BMC-Tx) by using a point-of-care system on cardiac function and on the mobilization of BM-CPCs in patients with ischemic heart disease (IHD). Fifty-six patients with IHD were randomized to either receive freshly isolated BMC-Tx or a control group that did not receive cell therapy. Peripheral blood concentrations of CD34/45(+) and CD133/45(+) CPCs were measured by flow cytometry pre-, immediately post-, and at 3, 6, and 12 months postprocedure in both groups. Global ejection fraction and the size of infarct area were determined by left ventriculography. We observed in patients with IHD after intracoronary transplantation of autologous freshly isolated BMCs-Tx at 3 and 12 months follow-up a significant reduction of the size of infarct area and increase of global ejection fraction as well as infarct wall movement velocity. The mobilization of CD34/45(+) and CD133/45(+) BM-CPCs significantly increased at 3, 6, and 12 months after cell therapy when compared with baseline in patients with IHD, although no significant changes were observed between pre- and immediately postintracoronary cell therapy administration. In the control group without cell therapy, there was no significant difference of CD34/45(+) and CD133/45(+) BM-CPCs mobilization between pre- and at 3, 6, and 12 months postcoronary angiography. Intracoronary transplantation of autologous freshly isolated BMCs by using a point-of-care system in patients with IHD may enhance and prolong the mobilization of CD34/45(+) and CD133/45(+) BM-CPCs in peripheral blood and this might increase the regenerative potency in IHD.

Differential heart rate dynamics in transient left ventricular apical and midventricular ballooning

BACKGROUND

The aim of the present study was to assess potential differences in cardiac autonomic nervous modulation in patients with transient left ventricular apical ballooning syndrome (AB) and the midventricular variant (MB) of this syndrome.

OBJECTIVE

We hypothesized that differences in regional distribution of cardiac autonomic innervation in AB and MB may induce alterations in autonomic modulation, and we tested this assumption by using a combination of traditional and novel nonlinear parameters of heart rate variability (HRV).

METHODS

In a prospective single-center study, 49 consecutive patients with transient left ventricular dysfunction syndrome underwent Holter electrocardiographic recording on the third day after admission. A total of 27 recordings of patients with AB and 10 recordings of patients with MB were valid for analysis of HRV, nonlinear dynamic measures of HRV, detrended fluctuation analysis (DFA), and phase-rectified signal averaging (PRSA).

RESULTS

There were no significant differences in baseline clinical characteristics between AB and MB patients. Patients with MB showed significantly lower values for mean RR interval (835 ± 104 ms vs. 908 ± 118 ms; P < .05), 1/f power law slope (-1.28 ± 0.2 vs. -1.13 ± 0.2; P < .01), and deceleration capacity (DC) (4.6 ± 1.4 ms vs. 6.0 ± 1.4 ms; P < .01), and significantly higher values for low-frequency (LF) spectral component (5.3 ± 0.5 ln ms(2)/Hz vs. 4.8 ± 0.5 ln ms(2)/Hz), LF/high-frequency (HF) (1.7 ± 0.9 ms vs. 1.3 ± 0.6 ms; P < .05), and DFA α1 (1.09 ± 0.1 vs. 0.99 ± 0.1; P < .01) than patients with AB. There were no significant correlations between parameters of HRV, DFA, 1/f power law slope, and PRSA.

CONCLUSION

There are significant differences in heart rate dynamics between AB and MB syndromes. Patients with MB show stronger fractal correlations of heart rate dynamics. Thus, inhomogeneous efferent bilateral sympathetic coactivation and differences in reflex autonomic regulation may be underlying pathophysiological mechanisms for AB and MB syndromes.