The effect of hydroxychloroquine on cholesterol metabolism in statin treated patients after myocardial infarction

Background and aims

To evaluate the effect of hydroxychloroquine (HCQ) on serum and lipoprotein lipids and serum biomarkers of cholesterol synthesis and absorption in myocardial infarction patients with a high-dose statin.

Methods

Myocardial infarction patients (n = 59) with a constant statin dose were randomized to receive hydroxychloroquine 300 mg (n = 31) or placebo (n = 28) daily for six months and followed up for one year.

Results

Statin reduced total-c (-26 ± 22% in hydroxychloroquine and -28 ± 19% in placebo group, P = 0.931), LDL-c (-38 ± 26% vs. -44 ± 23%, respectively, P = 0.299), and cholesterol synthesis biomarkers zymostenol, desmosterol, and lathosterol ratios from baseline to one year (e.g., serum lathosterol ratio -17 ± 45% vs. -15 ± 41%, respectively, P < 0.001 for both, P = 0.623 between groups). Compensatorily, cholesterol absorption increased during the intervention (e.g., serum campesterol ratio 125 ± 90% vs. 113 ± 72%, respectively, P < 0.001 for both, P = 0.488 between groups). Hydroxychloroquine did not affect cholesterol concentrations or cholesterol absorption. It prevented the statin-induced increase in cholesterol precursor, desmosterol ratio, from six months to one year in the hydroxychloroquine group (P = 0.007 at one year compared to placebo).

Conclusions

Combined with a high-dose statin, hydroxychloroquine had no additional effect on serum cholesterol concentration or cholesterol absorption. However, the findings suggest that hydroxychloroquine interferes with lanosterol synthesis, and thereafter, it temporarily interferes with the cholesterol synthesis pathway, best seen in halting the increase of the desmosterol ratio.Trial Registration ClinicalTrials.gov Identifier: NCT02648464.

Novel Technologies in the Detection of Atrial Fibrillation: Review of Literature and Comparison of Different Novel Technologies for Screening of Atrial Fibrillation

Atrial fibrillation (AF) is globally the most common arrhythmia associated with significant morbidity and mortality. It impairs the quality of the patient's life, imposing a remarkable burden on public health, and the healthcare budget. The detection of AF is important in the decision to initiate anticoagulation therapy to prevent thromboembolic events. Nonetheless, AF detection is still a major clinical challenge as AF is often paroxysmal and asymptomatic. AF screening recommendations include opportunistic or systematic screening in patients ≥65 years of age or in those individuals with other characteristics pointing to an increased risk of stroke. The popularities of well-being and taking personal responsibility for one's own health are reflected in the continuous development and growth of mobile health technologies. These novel mobile health technologies could provide a cost-effective solution for AF screening and an additional opportunity to detect AF, particularly its paroxysmal and asymptomatic forms.

Percutaneous coronary intervention with drug-coated balloon-only strategy combined with single antiplatelet treatment in patients at high bleeding risk: Single center experience of a novel concept

OBJECTIVES

At least 1 month of dual antiplatelet therapy is required after coronary stenting. The aim of this all-comers retrospective registry study was to assess the efficacy and safety of percutaneous coronary intervention (PCI) using drug-coated balloon (DCB) with single antiplatelet treatment (SAPT).

METHODS

Between 2011 and 2020, 232 PCIs were performed in 172 patients using the DCB-only strategy and discharged with SAPT.

RESULTS

The mean age of the patients was 75 ± 11 years and 59% were male. The clinical presentation was stable coronary artery disease (CAD) in 42% of the patients and acute coronary syndrome (ACS) in 58%. The lesions were mainly de novo (96%). The majority (58%) of treated lesions were in large coronary arteries (≥3.0 mm). Most (87%) of the patients were at high bleeding risk (HBR) with at least one major or two minor Academic Research Consortium (ARC) risk factors for bleeding. Periprocedural DAPT was used in 49% of the patients. The 12-month major adverse cardiac events (MACE, the composition of cardiovascular death, nonfatal myocardial infarction, and target-lesion revascularization) rate was 1.4% in stable CAD and 7.1% in ACS. The 12-month all-cause mortality after DBC only + SAPT strategy was 4.1% in stable CAD and 12.1% in ACS. The rate of ischemia-driven target lesion revascularisation (TLR) was 0% in stable CAD and 3.0% in ACS at 12 months. The 12-month rate of significant bleeding (BARC type 2-5) was 10.5%. There were no acute or subacute vessel closures.

CONCLUSIONS

Despite the aged patient population with comorbidities, the TLR, MACE, and bleeding rates were low with DCB-only PCI combined with SAPT. This novel approach could reduce the post-PCI bleeding risk in patients with CAD and HBR compared to stenting.

Drug-coated balloon-only strategy for percutaneous coronary intervention of de novo left main coronary artery disease: the importance of proper lesion preparation

This retrospective single-center registry study included all consecutive patients who underwent percutaneous coronary intervention (PCI) for a de novo left main coronary artery lesion using drug coated-balloon (DCB)-only strategy between August 2011 and December 2018. To best of our knowledge, no previous studies of DCB-only strategy of treating de novo left main coronary artery disease, exist. The primary endpoint was major adverse cardiovascular events (MACEs) including cardiac death, non-fatal myocardial infarction, and target lesion revascularization (TLR). The cohort was divided into two groups depending on weather the lesion preparation was done according to the international consensus group guidelines. Sixty-six patients (mean age 75±8.6, 72% male), 52% of whom had acute coronary syndrome, underwent left main PCI with the DCB-only strategy. No procedural mortality and no acute closures of the treated left main occurred. At 12 months, MACE and TLR occurred in 24% and 6% of the whole cohort, respectively. If the lesion preparation was done according to the guidelines, the MACE and TLR rates were 21.2% and 1.9%. Left main PCI with the DCB only-strategy is safe leading to acceptable MACE and low TLR rates at one year, if the lesion preparation is done according to the guidelines.

Technical success, clinical efficacy, and insight into the causes of restenosis after the percutaneous coronary intervention of de novo coronary artery lesions using a paclitaxel-coated balloon with citrate ester excipient

Objectives

The aim of this all-comers registry study was to investigate the technical success, clinical efficacy, and safety of a drug-coated balloon (DCB) with paclitaxel combined with citrate ester excipient (CEE) in percutaneous coronary intervention (PCI) of de novo coronary lesions in an all-comers population.

Materials and methods

A total of 338 consecutive PCIs using the DCB (CEE)-only approach comprising 406 de novo lesions were included in the study. Technical success was determined by the successful delivery of the device and no need for bailout stenting.

Results

The mean follow-up time was 25 ± 12 months. The mean age of patients was 71 ± 11 years, and 48% had the acute coronary syndrome. A total of 55% of the patients were at risk of factor bleeding. The delivery of DCB was successful in 98% of cases. The overall technical success rate was 83%. Bailout stenting was used in 9% of lesions. Rotational atherectomy was used in 11% of cases before the DCB-only approach. The mean diameter of the DCBs used was 2.7 ± 0.5 mm and 38% of DCBs were large (≥3.0 mm). The 12-month MACE rates were 5.4 ± 1.7 and 18.3 ± 3.1% in stable CAD and in ACS, respectively. The respective target lesion revascularization (TLR) rates were 3.0 ± 1.3 and 8.5 ± 2.3%. Unacceptable acute recoil (>30%) was found in 74% of cases that needed repeat revascularization. No acute vessel closures occurred after DCB treatment.

Conclusion

The DCB-only strategy using a paclitaxel-coated (CEE) device was technically feasible, safe, and effective in an all-comers population. Acute recoil was found as a significant cause of restenosis after the DCB-only strategy.

Incidence of Sudden Cardiac Death and Life-Threatening Arrhythmias in Clinically Manifest Cardiac Sarcoidosis With and Without Current Indications for an Implantable Cardioverter Defibrillator

BACKGROUND

Cardiac sarcoidosis (CS) predisposes to sudden cardiac death (SCD). Guidelines for implantable cardioverter defibrillators (ICDs) in CS have been issued by the Heart Rhythm Society in 2014 and the American College of Cardiology/American Heart Association/Heart Rhythm Society consortium in 2017. How well they discriminate high from low risk remains unknown.

METHODS

We analyzed the data of 398 patients with CS detected in Finland from 1988 through 2017. All had clinical cardiac manifestations. Histological diagnosis was myocardial in 193 patients (definite CS) and extracardiac in 205 (probable CS). Patients with and without Class I or IIa ICD indications at presentation were identified, and subsequent occurrences of SCD (fatal or aborted) and sustained ventricular tachycardia were recorded, as were ICD indications emerging first on follow-up.

RESULTS

Over a median of 4.8 years, 41 patients (10.3%) had fatal (n=8) or aborted (n=33) SCD, and 98 (24.6%) experienced SCD or sustained ventricular tachycardia as the first event. By the Heart Rhythm Society guideline, Class I or IIa ICD indications were present in 339 patients (85%) and absent in 59 (15%), of whom 264 (78%) and 30 (51%), respectively, received an ICD. Cumulative 5-year incidence of SCD was 10.7% (95% CI, 7.4%-15.4%) in patients with ICD indications versus 4.8% (95% CI, 1.2%-19.1%) in those without (χ2=1.834, P=0.176). The corresponding rates of SCD were 13.8% (95% CI, 9.1%-21.0%) versus 6.3% (95% CI, 0.7%-54.0%; χ2=0.814, P=0.367) in definite CS and 7.6% (95% CI, 3.8%-15.1%) versus 3.3% (95% CI, 0.5%-22.9%; χ2=0.680, P=0.410) in probable CS. In multivariable regression analysis, SCD was predicted by definite histological diagnosis (P=0.033) but not by Class I or IIa ICD indications (P=0.210). In patients without ICD indications at presentation, 5-year incidence of SCD, sustained ventricular tachycardia, and emerging Class I or IIa indications was 53% (95% CI, 40%-71%). By the American College of Cardiology/American Heart Association/Heart Rhythm Society guideline, all patients with complete data (n=245) had Class I or IIa indications for ICD implantation.

CONCLUSIONS

Current ICD guidelines fail to distinguish a truly low-risk group of patients with clinically manifest CS, the 5-year risk of SCD approaching 5% despite absent ICD indications. Further research is needed on prognostic factors, including the role of diagnostic histology. Meanwhile, all patients with CS presenting with clinical cardiac manifestations should be considered for an ICD implantation.

Continuous mHealth Patch Monitoring for the Algorithm-Based Detection of Atrial Fibrillation: Feasibility and Diagnostic Accuracy Study

Background

The detection of atrial fibrillation (AF) is a major clinical challenge as AF is often paroxysmal and asymptomatic. Novel mobile health (mHealth) technologies could provide a cost-effective and reliable solution for AF screening. However, many of these techniques have not been clinically validated.

Objective

The purpose of this study is to evaluate the feasibility and reliability of artificial intelligence (AI) arrhythmia analysis for AF detection with an mHealth patch device designed for personal well-being.

Methods

Patients (N=178) with an AF (n=79, 44%) or sinus rhythm (n=99, 56%) were recruited from the emergency care department. A single-lead, 24-hour, electrocardiogram-based heart rate variability (HRV) measurement was recorded with the mHealth patch device and analyzed with a novel AI arrhythmia analysis software. Simultaneously registered 3-lead electrocardiograms (Holter) served as the gold standard for the final rhythm diagnostics.

Results

Of the HRV data produced by the single-lead mHealth patch, 81.5% (3099/3802 hours) were interpretable, and the subject-based median for interpretable HRV data was 99% (25th percentile=77% and 75th percentile=100%). The AI arrhythmia detection algorithm detected AF correctly in all patients in the AF group and suggested the presence of AF in 5 patients in the control group, resulting in a subject-based AF detection accuracy of 97.2%, a sensitivity of 100%, and a specificity of 94.9%. The time-based AF detection accuracy, sensitivity, and specificity of the AI arrhythmia detection algorithm were 98.7%, 99.6%, and 98.0%, respectively.

Conclusions

The 24-hour HRV monitoring by the mHealth patch device enabled accurate automatic AF detection. Thus, the wearable mHealth patch device with AI arrhythmia analysis is a novel method for AF screening.

Trial Registration

ClinicalTrials.gov NCT03507335; https://clinicaltrials.gov/ct2/show/NCT03507335

Drug-Coated Balloon for Small Coronary Artery Disease in Patients With and Without High-Bleeding Risk in the BASKET-SMALL 2 Trial

BACKGROUND

Patients at high-bleeding risk (HBR) undergoing percutaneous coronary intervention represent a challenging patient population. The use of drug-coated balloon (DCB) allows shorter duration of dual antiplatelet therapy compared with drug-eluting stents (DES) and reduces thrombotic risk due to the absence of a permanent implant. The present analysis aimed to investigate if the effect of DCB versus DES differed between patients with and without HBR treated with percutaneous coronary intervention in small coronary arteries.

METHODS

This prespecified subgroup analysis of a multicenter, randomized, noninferiority trial included 758 patients with de novo lesions in coronary vessels <3 mm and an indication for percutaneous coronary intervention, randomized to DCB (n=382) or second-generation DES (n=376). Patients were followed over 3 years for major adverse cardiac events.

RESULTS

Of the 758 patients randomized, 155 (20%) had HBR; these patients had higher mortality at 3 years (hazard ratio [95% CI], 3.09 [1.78-5.36]; P<0.001). Rates of major bleeding events were overall low but tended to be lower after DCB versus DES (1.6% versus 3.7%; P=0.064), were similar in patients with HBR (4.5% versus 3.4%) but less frequent in DCB-versus DES-treated patients without HBR (0.9% versus 3.8%). There was no difference in major adverse cardiac events between DCB and DES regardless of bleeding risk (HBR, hazard ratio: 1.16 [0.51-2.62]; P=0.719 versus non-HBR, 0.96 [0.62-1.49]; P=0.863).

CONCLUSIONS

DCBs were similarly safe and effective as current-generation DES in the treatment of coronary arteries <3 mm, regardless of bleeding risk. In patients treated with DCB, there was a trend towards a reduction of severe bleeding events at 3 years.

REGISTRATION

URL: https://www.

CLINICALTRIALS

gov; Unique identifier: NCT01574534.

Continuous 24-h Photoplethysmogram Monitoring Enables Detection of Atrial Fibrillation

Aim: Atrial fibrillation (AF) detection is challenging because it is often asymptomatic and paroxysmal. We evaluated continuous photoplethysmogram (PPG) for signal quality and detection of AF.

Methods: PPGs were recorded using a wrist-band device in 173 patients (76 AF, 97 sinus rhythm, SR) for 24 h. Simultaneously recorded 3-lead ambulatory ECG served as control. The recordings were split into 10-, 20-, 30-, and 60-min time-frames. The sensitivity, specificity, and F1-score of AF detection were evaluated for each time-frame. AF alarms were generated to simulate continuous AF monitoring. Sensitivities, specificities, and positive predictive values (PPVs) of the alarms were evaluated. User experiences of PPG and ECG recordings were assessed. The study was registered in the Clinical Trials database (NCT03507335).

Results: The quality of PPG signal was better during night-time than in daytime (67.3 ± 22.4% vs. 30.5 ± 19.4%, p < 0.001). The 30-min time-frame yielded the highest F1-score (0.9536), identifying AF correctly in 72/76 AF patients (sensitivity 94.7%), only 3/97 SR patients receiving a false AF diagnosis (specificity 96.9%). The sensitivity and PPV of the simulated AF alarms were 78.2 and 97.2% at night, and 49.3 and 97.0% during the daytime. 82% of patients were willing to use the device at home.

Conclusion: PPG wrist-band provided reliable AF identification both during daytime and night-time. The PPG data’s quality was better at night. The positive user experience suggests that wearable PPG devices could be feasible for continuous rhythm monitoring.

Automatic Mobile Health Arrhythmia Monitoring for the Detection of Atrial Fibrillation: Prospective Feasibility, Accuracy, and User Experience Study

Background

Atrial fibrillation (AF) is the most common tachyarrhythmia and associated with a risk of stroke. The detection and diagnosis of AF represent a major clinical challenge due to AF’s asymptomatic and intermittent nature. Novel consumer-grade mobile health (mHealth) products with automatic arrhythmia detection could be an option for long-term electrocardiogram (ECG)-based rhythm monitoring and AF detection.

Objective

We evaluated the feasibility and accuracy of a wearable automated mHealth arrhythmia monitoring system, including a consumer-grade, single-lead heart rate belt ECG device (heart belt), a mobile phone application, and a cloud service with an artificial intelligence (AI) arrhythmia detection algorithm for AF detection. The specific aim of this proof-of-concept study was to test the feasibility of the entire sequence of operations from ECG recording to AI arrhythmia analysis and ultimately to final AF detection.

Methods

Patients (n=159) with an AF (n=73) or sinus rhythm (n=86) were recruited from the emergency department. A single-lead heart belt ECG was recorded for 24 hours. Simultaneously registered 3-lead ECGs (Holter) served as the gold standard for the final rhythm diagnostics and as a reference device in a user experience survey with patients over 65 years of age (high-risk group).

Results

The heart belt provided a high-quality ECG recording for visual interpretation resulting in 100% accuracy, sensitivity, and specificity of AF detection. The accuracy of AF detection with the automatic AI arrhythmia detection from the heart belt ECG recording was also high (97.5%), and the sensitivity and specificity were 100% and 95.4%, respectively. The correlation between the automatic estimated AF burden and the true AF burden from Holter recording was >0.99 with a mean burden error of 0.05 (SD 0.26) hours. The heart belt demonstrated good user experience and did not significantly interfere with the patient’s daily activities. The patients preferred the heart belt over Holter ECG for rhythm monitoring (85/110, 77% heart belt vs 77/109, 71% Holter, P=.049).

Conclusions

A consumer-grade, single-lead ECG heart belt provided good-quality ECG for rhythm diagnosis. The mHealth arrhythmia monitoring system, consisting of heart-belt ECG, a mobile phone application, and an automated AF detection achieved AF detection with high accuracy, sensitivity, and specificity. In addition, the mHealth arrhythmia monitoring system showed good user experience.

Trial Registration

ClinicalTrials.gov NCT03507335; https://clinicaltrials.gov/ct2/show/NCT03507335

Wrist Band Photoplethysmography Autocorrelation Analysis Enables Detection of Atrial Fibrillation Without Pulse Detection

Atrial fibrillation is often asymptomatic and intermittent making its detection challenging. A photoplethysmography (PPG) provides a promising option for atrial fibrillation detection. However, the shapes of pulse waves vary in atrial fibrillation decreasing pulse and atrial fibrillation detection accuracy. This study evaluated ten robust photoplethysmography features for detection of atrial fibrillation. The study was a national multi-center clinical study in Finland and the data were combined from two broader research projects (NCT03721601, URL: https://clinicaltrials.gov/ct2/show/NCT03721601 and NCT03753139, URL: https://clinicaltrials.gov/ct2/show/NCT03753139). A photoplethysmography signal was recorded with a wrist band. Five pulse interval variability, four amplitude features and a novel autocorrelation-based morphology feature were calculated and evaluated independently as predictors of atrial fibrillation. A multivariate predictor model including only the most significant features was established. The models were 10-fold cross-validated. 359 patients were included in the study (atrial fibrillation n = 169, sinus rhythm n = 190). The autocorrelation univariate predictor model detected atrial fibrillation with the highest area under receiver operating characteristic curve (AUC) value of 0.982 (sensitivity 95.1%, specificity 93.7%). Autocorrelation was also the most significant individual feature (p < 0.00001) in the multivariate predictor model, detecting atrial fibrillation with AUC of 0.993 (sensitivity 96.4%, specificity 96.3%). Our results demonstrated that the autocorrelation independently detects atrial fibrillation reliably without the need of pulse detection. Combining pulse wave morphology-based features such as autocorrelation with information from pulse-interval variability it is possible to detect atrial fibrillation with high accuracy with a commercial wrist band. Photoplethysmography wrist bands accompanied with atrial fibrillation detection algorithms utilizing autocorrelation could provide a computationally very effective and reliable wearable monitoring method in screening of atrial fibrillation.

Hydroxychloroquine reduces interleukin-6 levels after myocardial infarction: The randomized, double-blind, placebo-controlled OXI pilot trial

OBJECTIVES

To determine the anti-inflammatory effect and safety of hydroxychloroquine after acute myocardial infarction.

METHOD

In this multicenter, double-blind, placebo-controlled OXI trial, 125 myocardial infarction patients were randomized at a median of 43 h after hospitalization to receive hydroxychloroquine 300 mg (n = 64) or placebo (n = 61) once daily for 6 months and, followed for an average of 32 months. Laboratory values were measured at baseline, 1, 6, and 12 months.

RESULTS

The levels of interleukin-6 (IL-6) were comparable at baseline between study groups (p = 0.18). At six months, the IL-6 levels were lower in the hydroxychloroquine group (p = 0.042, between groups), and in the on-treatment analysis, the difference at this time point was even more pronounced (p = 0.019, respectively). The high-sensitivity C-reactive protein levels did not differ significantly between study groups at any time points. Eleven patients in the hydroxychloroquine group and four in the placebo group had adverse events leading to interruption or withdrawal of study medication, none of which was serious (p = 0.10, between groups).

CONCLUSIONS

In patients with myocardial infarction, hydroxychloroquine reduced IL-6 levels significantly more than did placebo without causing any clinically significant adverse events. A larger randomized clinical trial is warranted to prove the potential ability of hydroxychloroquine to reduce cardiovascular endpoints after myocardial infarction.

Manifestations and Outcome of Cardiac Sarcoidosis and Idiopathic Giant Cell Myocarditis by 25-Year Nationwide Cohorts

Background Cardiac sarcoidosis (CS) and giant cell myocarditis (GCM) share many histopathologic and clinical features. Whether they are parts of a one-disease continuum has been discussed. Methods and Results We compared medical record data of 351 CS and 28 GCM cases diagnosed in Finland since the late 1980s and followed until February 2018 for a composite end point of cardiac death, aborted sudden death, and heart transplantation. Heart failure was the presenting manifestation in 50% versus 15% (P<0.001), and high-grade atrioventricular block in 21% versus 43% (P=0.044), of GCM and CS, respectively. At presentation, left ventricular ejection fraction was ≤50% in 81% of cases of GCM versus in 48% of CS (P=0.004). The median (interquartile range) of plasma NT-proBNP (N-terminal pro-B-type natriuretic peptide) was 5273 (2782-11309) ng/L on admission in GCM versus 859 (290-1950) ng/L in CS (P<0.001), and cardiac troponin T exceeded 50 ng/L in 17 of 19 cases of GCM versus in 48 of 239 cases of CS (P<0.001). The 5-year estimate of event-free survival was 77% (95% CI, 72%-82%) in CS versus 27% (95% CI, 10%-45%) in GCM (P<0.001). By Cox regression analysis, GCM predicted cardiac events with a hazard ratio of 5.16 (95% CI, 2.82-9.45), which, however, decreased to 1.58 (95% CI, 0.71-3.52) after inclusion of markers of myocardial injury and dysfunction in the model. Conclusions GCM differs from CS in presenting with more extensive myocardial injury and having worse long-term outcome. Yet the key determinant of prognosis appears to be the extent of myocardial injury rather than the histopathologic diagnosis.

Necklace-embedded electrocardiogram for the detection and diagnosis of atrial fibrillation

BACKGROUND

Atrial fibrillation (AF) is the major cause of stroke since approximately 25% of all strokes are of cardioembolic-origin. The detection and diagnosis of AF are often challenging due to the asymptomatic and intermittent nature of AF.

HYPOTHESIS

A wearable electrocardiogram (ECG)-device could increase the likelihood of AF detection. The aim of this study was to evaluate the feasibility and reliability of a novel, consumer-grade, single-lead ECG recording device (Necklace-ECG) for screening, identifying and diagnosing of AF both by a cardiologist and automated AF-detection algorithms.

METHODS

A thirty-second ECG was recorded with the Necklace-ECG device from two positions; between the palms (palm) and between the palm and the chest (chest). Simultaneously registered 3-lead ECGs (Holter) served as a golden standard for the final rhythm diagnosis. Two cardiologists interpreted independently in a blinded fashion the Necklace-ECG recordings from 145 patients (66 AF and 79 sinus rhythm, SR). In addition, the Necklace-ECG recordings were analyzed with an automatic AF detection algorithm.

RESULTS

Two cardiologists diagnosed the correct rhythm of the interpretable Necklace-ECG with a mean sensitivity of 97.2% and 99.1% (palm and chest, respectively) and specificity of 100% and 98.5%. The automatic arrhythmia algorithm detected the correct rhythm with a sensitivity of 94.7% and 98.3% (palm and chest) and specificity of 100% of the interpretable measurements.

CONCLUSIONS

The novel Necklace-ECG device is able to detect AF with high sensitivity and specificity as evaluated both by cardiologists and an automated AF-detection algorithm. Thus, the wearable Necklace-ECG is a new, promising method for AF screening.

CLINICAL TRIAL REGISTRATION

Study was registered in the ClinicalTrials.gov database (NCT03753139).

Wrist band photoplethysmography in detection of individual pulses in atrial fibrillation and algorithm-based detection of atrial fibrillation

AIMS

Atrial fibrillation (AF) is the most common tachyarrhythmia and a significant cause of cardioembolic strokes. Atrial fibrillation is often intermittent and asymptomatic making detection a major clinical challenge. We evaluated a photoplethysmography (PPG) wrist band in individual pulse detection in patients with AF and tested the reliability of two commonly used algorithms for AF detection.

METHODS AND RESULTS

A 5-min PPG was recorded from patients with AF or sinus rhythm (SR) with a wrist band and analysed with two AF detection algorithms; AFEvidence and COSEn. Simultaneously registered electrocardiogram served as the golden standard for rhythm analysis and was interpreted by two cardiologists. The study population consisted of 213 (106 AF, 107 SR) patients. The wrist band PPG achieved individual pulse detection with a sensitivity of 91.7 ± 11.2% and a positive predictive value (PPV) of 97.5 ± 4.6% for AF, with a sensitivity of 99.4 ± 1.5% [7.7% (95% confidence interval, 95% CI 5.5% to 9.9%); P < 0.001] and PPV of 98.1 ± 4.1% [0.6% (95% CI -0.6% to 1.7%); P = 0.350] for SR. The pulse detection sensitivity was lower 86.7 ± 13.9% with recent-onset AF (AF duration <48 h, n = 43, 40.6%) as compared to late AF (≥48 h, n = 63, 59.4%) with 95.1 ± 7.2% [-8.3% (95% CI -12.9% to -3.7%); P = 0.001]. For the detection of AF from the wrist band PPG, the sensitivities were 96.2%/95.3% and specificity 98.1% with two algorithms.

CONCLUSION

The wrist band PPG enabled accurate algorithm-based detection of AF with two AF detection algorithms and high individual pulse detection. Algorithms allowed accurate detection of AF from the PPG. A PPG wrist band provides an easy solution for AF screening.

CONTEMPORARY RADIATION DOSES IN INTERVENTIONAL CARDIOLOGY: A NATIONWIDE STUDY OF PATIENT SKIN DOSES IN FINLAND

In contemporary interventional cardiology, for typical elderly patients, the most severe radiation-related harm to patients can be considered to come from skin exposures. In this paper, maximum local skin doses in cardiological procedures are explored with Gafchromic film dosimetry. Film and reader calibrations and reading were performed at the Secondary Standards Dosimetry Laboratory of the Radiation and Nuclear Safety Authority (STUK), and data were gathered from seven hospitals in Finland. As alert levels for early transient erythema, 200 Gycm2 kerma area product (KAP) and 2000 mGy air kerma levels for transcatheter aortic valve implantations (TAVI) procedures are proposed. The largest doses were measured in TAVI (4158.8 mGy) and percutaneous coronary interventions (PCI) (941.68 mGy). Accuracies of the GE DoseWatch and Siemens CareMonitor skin dose estimates were reasonable, but more results are needed to reliably assess and validate the tools' capabilities and reliabilities. Uncertainty of the Gafchromic dosimetry was estimated as 9.1% for a calibration with seven data points and 19.3% for a calibration with five data points.

224Wireless ECG embedded in a necklace enables reliable detection of atrial fibrillation

Funding Acknowledgements

Goverment grant, Heart2save Ltd cooperation.

Background/Introduction:

Atrial fibrillation (AF) is the most common arrhythmia and a fast-growing public health problem worldwide. Main and the most severe complication of AF is an embolic stroke. Approximately 25% of all strokes are caused by AF. AF is often symptomless and intermittent, making its detection and diagnosing challenging. Many AF patients have both symptomatic and asymptomatic periods of arrhythmia. In addition, during the early stage of the disease, AF is often paroxysmal making the diagnosis of AF a major clinical challenge.

Purpose

Wearable ECG devices could enable repetitive rhythm monitoring over a long term and thus improve the probability of AF detection. Wearable devices have the advantage of being easily available. However, they also need to be reliable and their design should appeal customers. Our aim was to study the suitability and reliability of novel measurement technique (necklace-ECG, Figure1) for the diagnosis of AF.

Methods

The study population consisted of 145 adult volunteers at Kuopio University Hospital emergency department (66 AF and 79 sinus rhythm (SR), diagnosed from continuous 3-lead ECG recording. All study subjects performed a thirty-second self-performed ECG recording with a single-lead necklace-embedded ECG recorder (necklace-ECG) keeping the recorder between palms of their hands. The ECG recordings were analyzed with automatic AF detection algorithm. Two cardiologists interpreted independently in blinded fashion the necklace-ECG recordings and simultaneously registered 3-lead ECGs which served as golden standard for the final rhythm diagnosis.

Results

Necklace-ECG produced an interpretable ECG recording in 91.0%/86.2% patients (Doc1/Doc2, respectively). Additionally, 93.1% of ECG recordings were interpretable by the automatic analysis service (98.7% in SR patients and 86.4% of AF patients).

Base on the necklace ECG recording, cardiologists were able to diagnose AF with sensitivity of 98.2%/96.3% (Doc1/Doc2, respectively) and specificity of 100% (Doc1 and Doc2, respectively). The automatic arrhythmia algorithm diagnosed AF with sensitivity of 94.7% and specificity of 100%.

Conclusions

The necklace-ECG device produces ECG recording with sufficient quality for the detection of AF with good sensitivity and specificity as evaluated both by cardiologist and automated AF-detection algorithm. Thus, wearable necklace-ECG provides a new and easy method for screening, identifying and diagnosing AF.

Abstract Figure 1

Outcomes of lipid control in secondary prevention of coronary artery disease in Finland: A 24-month follow-up after acute coronary syndrome

BACKGROUND AND AIMS

Ischemic heart diseases are the main cause of death worldwide, therefore secondary prevention and treatment of coronary artery disease (CAD) are highly significant for public health and mortality. The objective of this study is to evaluate LDL cholesterol (LDL-C) levels as outcomes of secondary prevention of CAD in Finland up to 24 months after being diagnosed with acute coronary syndrome (ACS). This retrospective analysis of patients with ACS was conducted in two areas of Finland that have a combined population of 400,000.

METHODS

The data used in the study covered all outpatient visits, inpatient episodes, prescriptions and LDL-C results for ACS patients during 2011-2015. To evaluate the outcome of the prevention, three separate measurements of patients' LDL-C levels were considered: baseline, first follow-up and final follow-up. The factors associated with reaching treatment goal were identified using logistic regression analysis.

RESULTS

32% of ACS patients achieved the treatment goal (LDL-C <1.8 mmol/l) at the end of the 24-month follow-up period, but 21% of patients fluctuated between being on and above target.

CONCLUSION

Two thirds of CAD patients with ACS and on statin therapy do not achieve LDL-C treatment target recommended by the guidelines. Since LDL-C levels fluctuate in the follow-up, a low level during the first 12 months after the acute event does not guarantee the maintenance of the results in the long term. Hence, LDL-C levels should be monitored at least on an yearly basis on follow-ups, and treatment adapted accordingly.

CONTEMPORARY RADIATION DOSES IN INTERVENTIONAL CARDIOLOGY: A NATIONWIDE STUDY OF PATIENT DOSES IN FINLAND

The amount of interventional procedures such as percutaneous coronary intervention (PCI), transcatheter aortic valve implantation (TAVI), pacemaker implantation (PI) and ablations has increased within the previous decade. Simultaneously, novel fluoroscopy mainframes enable lower radiation doses for patients and operators. Therefore, there is a need to update the existing diagnostic reference levels (DRLs) and propose new ones for common or recently introduced procedures. We sought to assess patient radiation doses in interventional cardiology in a large sample from seven hospitals across Finland between 2014 and 2016. Data were used to set updated national DRLs for coronary angiographies (kerma-air product (KAP) 30 Gycm2) and PCIs (KAP 75 cm2), and novel levels for PIs (KAP 3.5 Gycm2), atrial fibrillation ablation procedures (KAP 25 Gycm2) and TAVI (KAP 90 Gycm2). Tentative KAP values were set for implantations of cardiac resynchronization therapy devices (CRT, KAP 22 Gycm2), electrophysiological treatment of atrioventricular nodal re-entry tachycardia (6 Gycm2) and atrial flutter procedures (KAP 16 Gycm2). The values for TAVI and CRT device implantation are published for the first time on national level. Dose from image acquisition (cine) constitutes the major part of the total dose in coronary and atrial fibrillation ablation procedures. For TAVI, patient weight is a good predictor of patient dose.

Drug-coated balloon for treatment of de-novo coronary artery lesions in patients with high bleeding risk (DEBUT): a single-blind, randomised, non-inferiority trial

BACKGROUND

The optimal technique of percutaneous coronary intervention in patients at high bleeding risk is not known. The hypothesis of the DEBUT trial was that percutaneous coronary intervention with drug-coated balloons is non-inferior to percutaneous coronary intervention with bare-metal stents for this population.

METHODS

The DEBUT trial is a randomised, single-blind non-inferiority trial done at five sites in Finland. Patients were eligible if they had an ischaemic de-novo lesion in a coronary artery or bypass graft that could be treated with drug-coated balloons, at least one risk factor for bleeding, and a reference vessel diameter of 2·5-4·0 mm. Those with myocardial infarction with ST-elevation, bifurcation lesions needing a two-stent technique, in-stent restenosis, and flow-limiting dissection or substantial recoil (>30%) of the target lesion after predilation were excluded. After successful predilation of the target lesion, patients were randomly assigned (1:1), by use of a computer-generated random sequence, to percutaneous coronary intervention with a balloon coated with paclitaxel and iopromide or a bare-metal stent. The primary outcome was major adverse cardiac events at 9 months. Non-inferiority was shown if the absolute risk difference was no more than 3%. All prespecified analyses were done in the intention-to-treat population. This trial is registered with ClinicalTrials.gov, number NCT01781546.

FINDINGS

Between May 22, 2013, and Jan 16, 2017, 220 patients were recruited for the study and 208 patients were assigned to percutaneous coronary intervention with drug-coated balloon (n=102) or bare metal stent (n=106). At 9 months, major adverse cardiac events had occurred in one patient (1%) in the drug-coated balloon group and in 15 patients (14%) in the bare-metal stent group (absolute risk difference -13·2 percentage points [95% CI -6·2 to -21·1], risk ratio 0·07 [95% CI 0·01 to 0·52]; p<0·00001 for non-inferiority and p=0·00034 for superiority). Two definitive stent thrombosis events occurred in the bare metal stent group but no acute vessel closures in the drug-coated balloon group.

INTERPRETATIONS

Percutaneous coronary intervention with drug-coated balloon was superior to bare-metal stents in patients at bleeding risk. The drug-coated balloon-only coronary intervention is a novel strategy to treat this difficult patient population. Comparison of this approach to the new generation drug-eluting stents is warranted in the future.

FUNDING

B Braun Medical AG, AstraZeneca, and Competitive State Research Funding of the Kuopio University Hospital Catchment Area.

Sudden death in cardiac sarcoidosis: an analysis of nationwide clinical and cause-of-death registries

Aims

The present study was done to assess the role of sudden cardiac death (SCD) among the presenting manifestations of and fatalities from cardiac sarcoidosis (CS).

Methods and results

We analysed altogether 351 cases of CS presenting from year 1998 through 2015 in Finland. There were 262 patients with a clinical diagnosis and treatment of CS, 27 patients with an initial lifetime diagnosis of giant cell myocarditis that was later converted to CS, and 62 cases detected at autopsy and identified by screening >820 000 death certificates from the national cause-of-death registry. The total case series comprised 253 females and 98 males aged on average 52 years at presentation. High-grade atrioventricular block was the most common first sign of CS (n = 147, 42%) followed by heart failure (n = 58, 17%), unexpected fatal (n = 38) or aborted (n = 12) SCD (14%), and sustained ventricular tachycardia (n = 48, 14%). Severe coronary artery disease was found at autopsy concomitant with CS in four of the 38 cases presenting with fatal SCD. Of all deaths recorded till the end of 2015, 64% (n = 54/84) were unexpected SCDs from CS that had either been silent during life or defied all attempts at diagnosis. The Kaplan–Meier estimate (95% CI) of survival from symptom onset was 85% (80–90%) at 5 years and 76% (68–84%) at 10 years.

Conclusion

Together fatal and aborted SCD constitute 14% of the presenting manifestations of CS. Nearly two-thirds of all fatalities from CS are caused by undiagnosed granulomas in the heart.

Effectiveness of the Chest Strap Electrocardiogram to Detect Atrial Fibrillation

Atrial fibrillation (AF) is a significant cause of cardioembolic strokes. AF is often symptomless and intermittent, making its detection challenging. The aim of this study was to assess the possibility to use a chest strap (Suunto Movesense) to detect AF both by cardiologists and automated algorithms. A single channel electrocardiogram (ECG) from a chest strap of 220 patients (107 AF and 111 sinus rhythm SR with 2 inconclusive rhythms) were analyzed by 2 cardiologists (Doc1 and Doc2) and 2 different algorithms (COSEn and AFEvidence). A 3-lead Holter served as the gold standard ECG for rhythm analysis. Both cardiologists evaluated the quality of the chest strap ECG to be superior to the quality of the Holter ECG; p <0.05/p <0.001 (Doc1/Doc 2). Accurate automated algorithm-based AF detection was achieved with sensitivity of 95.3%/96.3% and specificity of 95.5/98.2% with 2 AF detection algorithms from chest strap and 93.5%/97.2% and 98.2%/95.5% from Holter, respectively. P waves were detectable in 93.7% (Doc1) and 94.6% (Doc2) of the cases from the chest strap ECG with sinus rhythm and 98.2% (Doc1) and 95.5% (Doc2) from the Holter (p = n.s). In conclusion, the ECGs from both methods enabled AF detection by a cardiologist and by automated algorithms. Both methods studied enabled P-wave detection in sinus rhythm.

Improved endothelialization of small-diameter ePTFE vascular grafts through growth factor therapy

Background

Prosthetic vascular grafts in humans characteristically lack confluent endothelialization regardless of the duration of implantation. Use of high-porosity grafts has been proposed as a way to induce endothelialization through transgraft capillarization, although early experiments failed to show increased healing in man.

Objectives

We hypothesized that transduction of tissues around the prosthetic conduit with vectors encoding VEGF receptor-2 (VEGFR2) ligands would augment transinterstitial capillarization and induce luminal endothelialization of high-porosity ePTFE grafts.

Methods

Fifty-two NZW rabbits received 87 ePTFE uni- or bilateral end-to-end interposition grafts in carotid arteries. Rabbits were randomized to local therapy with adenoviruses encoding AdVEGF-A165, AdVEGF-A109 or control AdLacZ and analyzed at 6 and 28 days after surgery by contrast-enhanced ultrasound and histology.

Results

AdVEGF-A165 and AdVEGF-A109 dramatically increased perfusion in perigraft tissues at 6 days (14.2 ± 3.6 or 16.7 ± 2.6-fold increases, P < 0.05 and P < 0.01). At 28 days, the effect was no longer significantly higher than baseline. At 6 days, no luminal endothelialization was observed in any of the groups. At 28 days, AdVEGF-A109- and AdVEGF-A165-treated animals showed enhanced ingrowth of transinterstitial capillaries (66.0 ± 13.7% and 77.4 ± 15.7% of graft thickness vs 44.7 ± 24.4% in controls, P < 0.05) and improved luminal endothelialization (11.2 ± 26.3% and 11.4 ± 22.2%, AdVEGF-A109 and AdVEGF-A165 vs 0% in controls, P < 0.05). No increased stenosis was observed in the treatment groups as compared to LacZ controls.

Conclusions

This study suggests that transient local overexpression of VEGFR2 ligands in the peri-implant tissues at the time of graft implantation is a novel strategy to increase endothelialization of high-porosity ePTFE vascular grafts and improve the patency of small-diameter vascular prostheses.

Adenoviral intramyocardial VEGF-DΔNΔC gene transfer increases myocardial perfusion reserve in refractory angina patients: a phase I/IIa study with 1-year follow-up

Aims

We evaluated for the first time the effects of angiogenic and lymphangiogenic AdVEGF-D^ΔNΔC gene therapy in patients with refractory angina.

Methods and results

Thirty patients were randomized to AdVEGF-D^ΔNΔC (AdVEGF-D) or placebo (control) groups. Electromechanical NOGA mapping and radiowater PET were used to identify hibernating viable myocardium where treatment was targeted. Safety, severity of symptoms, quality of life, lipoprotein(a) [Lp(a)] and routine clinical chemistry were measured. Myocardial perfusion reserve (MPR) was assessed with radiowater PET at baseline and after 3- and 12-months follow-up. Treatment was well tolerated. Myocardial perfusion reserve increased significantly in the treated area in the AdVEGF-D group compared with baseline (1.00 ± 0.36) at 3 months (1.31 ± 0.46, P = 0.045) and 12 months (1.44 ± 0.48, P = 0.009) whereas MPR in the reference area tended to decrease (2.05 ± 0.69, 1.76 ± 0.62, and 1.87 ± 0.69; baseline, 3 and 12 months, respectively, P = 0.551). Myocardial perfusion reserve in the control group showed no significant change from baseline to 3 and 12 months (1.26 ± 0.37, 1.57 ± 0.55, and 1.48 ± 0.48; respectively, P = 0.690). No major changes were found in clinical chemistry but anti-adenovirus antibodies increased in 54% of the treated patients compared with baseline. AdVEGF-D patients in the highest Lp(a) tertile at baseline showed the best response to therapy (MPR 0.94 ± 0.32 and 1.76 ± 0.41 baseline and 12 months, respectively, P = 0.023).

Conclusion

AdVEGF-D^ΔNΔC gene therapy was safe, feasible, and well tolerated. Myocardial perfusion increased at 1 year in the treated areas with impaired MPR at baseline. Plasma Lp(a) may be a potential biomarker to identify patients that may have the greatest benefit with this therapy.

Outcomes of Secondary Prevention among Coronary Heart Disease Patients in a High-Risk Region in Finland

Despite comprehensive national treatment guidelines, goals for secondary prevention of coronary heart disease (CHD) have not been sufficiently met everywhere in Finland. We investigated the recorded risk factor rates of CHD and their spatial differences in North Karelia Hospital District, which has a very high cardiovascular burden, in order to form a general view of the state of secondary prevention in a high-risk region. Appropriate disease codes of CHD-diagnoses and coding for percutaneous coronary intervention (PCI) and coronary artery bypass grafting (CABG) were used to identify from the electronic patient records the patient group eligible for secondary prevention. The cumulative incidence rate of new patients (n = 2556) during 2011–2014 varied from 1.9% to 3.5% between municipalities. The success in secondary prevention of CHD was assessed using achievement of treatment targets as defined in national guidelines. Health centres are administrated by municipalities whereupon the main reporting units were municipalities, together with composed classification of patients by age, gender and dwelling location. Health disparities between municipalities, settlement types and patient groups were found and are interpreted. Moreover, spatial high-risk and low-risk clusters of acute CHD were detected. The proportion of patients achieving the treatment targets of low-density lipoprotein cholesterol (LDL-C) varied from 21% to 38% between municipalities. Variation was also observed in the follow-up of patients; e.g., the rate of follow-up measurements of LDL-C in municipalities varied from 72% to 86%. Spatial variation in patients’ sociodemographic and neighbourhood characteristics and morbidity burden partly explain the differences in outcomes, but there are also very likely differences in the care process between municipalities which requires a study in its own right.

Percutaneous Coronary Intervention of Complex Calcified Lesions With Drug-Coated Balloon After Rotational Atherectomy

OBJECTIVES

We investigated the safety and efficacy of PCI using drug-coated balloon (DCB) after rotational atherectomy (rotablation) in a retrospective single center study in patients with calcified de novo coronary lesions. The majority of patients had an increased risk for bleeding.

BACKGROUND

DCB has been effective in the treatment of in-stent restenosis, small vessels, and bifurcations. DCB enables short one month dual antiplatelet treatment. No published data exist on the use of DCB after rotablation.

METHODS

82 PCIs were performed in 65 patients (mean age 72 ± 10 years) using rotablation followed by DCB treatment. The median follow-up time was 17 months. 82% of the patients had at least one risk factor for bleeding such as oral anticoagulation. 32% had an acute coronary syndrome. Median duration of dual antiplatelet treatment was 1 month.

RESULTS

MACE (the composite of cardiovascular death, ischemia-driven target-lesion revascularization [TLR] or non-fatal myocardial infarction) occurred in 14% and 20% of the patients at 12 and 24 months, respectively. The rate of ischemia-driven TLR was 1.5% at 12 months and 3.0% at 24 months. No acute closure of the treated vessel occurred. Bailout stenting was needed in 10% of the PCIs. The incidence of significant bleeding was 9% at 12 months.

CONCLUSIONS

This is the first study to show that PCI using DCB after preparation of calcified lesions with rotablation is safe and effective. This novel strategy may be considered especially in patients with a bleeding risk such as those using an oral anticoagulant.

Treatment of chronic total occlusions in native coronary arteries by drug-coated balloons without stenting - A feasibility and safety study

BACKGROUND

Chronic total occlusions remain one of the biggest challenges for interventional cardiologists and the high risk of restenosis and stent thrombosis is still a major problem. Drug-coated balloons showed favorable results for the treatment of in-stent restenosis and other lesion types. The aim of this study was to evaluate the feasibility and outcome of a drug-coated balloon only approach for chronic total occlusion.

METHODS

We included 34 patients with a native chronic total occlusion treated only by drug-coated balloons. A visual residual stenosis of 30% or less without major dissection was considered a satisfactory percutaneous intervention result according to the German Consensus Group recommendations for drug-coated balloon use. We collected clinical and procedural data. Angiograms were conducted during the procedure and at follow-up. Quantitative coronary analysis was performed and mean and minimal lumen diameter and late luminal changes were assessed.

RESULTS

The recanalization was considered satisfactory in 79.4% (n=27). Restenosis occurred in 11.8% (n=4) and reocclusion in 5.9% (n=2). Out of the 27 patients with a satisfactory initial result, 3.7% (n=1) had reocclusion and 3.7% (n=1) had restenosis. In the subgroup without satisfactory result (n=7), restenosis occurred in 3 patients (42.9%) and reocclusion in 1 patient (14.3%). A luminal increase was found in 67.6% (n=23) and mean late luminal gain was 0.11±0.49mm. Angina class improved significantly (p<0.001). There was no death or myocardial infarction.

CONCLUSIONS

Drug-coated balloon angioplasty without stenting is a feasible and well-tolerated treatment method for chronic total occlusions if the predilatation result is good.

Ultrasound imaging with bolus delivered contrast agent for the detection of angiogenesis and blood flow irregularities

Highly increased blood flow and vascularity after angiogenic gene therapy have raised concerns of shunting and hemangioma-like blood pool formation that might decrease effective perfusion and ruin the beneficial effects of the therapy. Contrast enhanced ultrasound is a promising noninvasive tool for studying skeletal muscle perfusion. The objectives of the present study were to test bolus and infusion administrations of ultrasound microbubble contrast media in imaging vascular growth in skeletal muscle and assess the functionality of vessels grown with angiogenic gene therapy. Contrast enhanced ultrasound was used to study changes in skeletal muscle perfusion in normal and gene-transduced rabbit hindlimbs 6 days after gene transfer. Adenoviral gene transfer of VEGF (10 e9–10 e11 viral particles) or β-galactosidase control gene (10 e11 viral particles) was done under anesthesia and induced up to 16-fold increases in relative tissue perfusion. Contrast intensity versus time curves were plotted and analyzed for contrast kinetics. Bolus administration of the contrast media was highly feasible in analyzing skeletal muscle blood flow and its kinetics. Maximal signal intensity of the bolus signal reflected relative changes in both blood flow and volume equally to the infusion method. Flow irregularities were detected after angiogenic gene therapy. In conclusion, bolus delivery of ultrasound contrast agent is highly feasible for the relative analysis of both quantity and quality of blood flow after angiogenic gene therapy. The kinetics of blood flow can and should be studied more extensively in both preclinical and clinical trials of angiogenic gene therapy since there is increasing evidence of flow irregularities in angiogenic vessels.

HIF-1α and HIF-2α induce angiogenesis and improve muscle energy recovery

BACKGROUND

Cardiovascular patients suffer from reduced blood flow leading to ischaemia and impaired tissue metabolism. Unfortunately, an increasing group of elderly patients cannot be treated with current revascularization methods. Thus, new treatment strategies are urgently needed. Hypoxia-inducible factors (HIFs) upregulate the expression of angiogenic mediators together with genes involved in energy metabolism and recovery of ischaemic tissues. Especially, HIF-2α is a novel factor, and only limited information is available about its therapeutic potential.

METHODS

Gene transfers with adenoviral HIF-1α and HIF-2α were performed into the mouse heart and rabbit ischaemic hindlimbs. Angiogenesis was evaluated by histology. Left ventricle function was analysed with echocardiography. Perfusion in rabbit skeletal muscles and energy recovery after electrical stimulation-induced exercise were measured with ultrasound and (31)P-magnetic resonance spectroscopy ((31)P-MRS), respectively.

RESULTS

HIF-1α and HIF-2α gene transfers increased capillary size up to fivefold in myocardium and ischaemic skeletal muscles. Perfusion in skeletal muscles was increased by fourfold without oedema. Especially, AdHIF-1α enhanced the recovery of ischaemic muscles from electrical stimulation-induced energy depletion. Special characteristic of HIF-2α gene transfer was a strong capillary growth in muscle connective tissue and that HIF-2α gene transfer maintained left ventricle function.

CONCLUSIONS

We conclude that both AdHIF-1α and AdHIF-2α gene transfers induced beneficial angiogenesis in vivo. Transient moderate increases in angiogenesis improved energy recovery after exercise in ischaemic muscles. This study shows for the first time that a moderate increase in angiogenesis is enough to improve tissue energy metabolism, which is potentially a very useful feature for cardiovascular gene therapy.

The bottleneck stent model for chronic myocardial ischemia and heart failure in pigs

A large animal model of chronic myocardial ischemia and heart failure is crucial for the development of novel therapeutic approaches. In this study we developed a novel percutaneous one- and two-vessel model for chronic myocardial ischemia using a stent coated with a polytetrafluoroethylene tube formed in a bottleneck shape. The bottleneck stent was implanted in the proximal left anterior descending (LAD) or proximal circumflex artery (LCX), or in both proximal LCX and mid LAD 1 wk later (2-vessel model), and pigs were followed for 4–5 wk. Ejection fraction (EF), infarct size, collateral growth, and myocardial perfusion were assessed. Pigs were given antiarrhythmic medication to prevent sudden death. The occlusion time of the bottleneck stent and the timing of myocardial infarction could be modulated by the duration of antiplatelet medication. Fractional flow reserve measurements and positron emission tomography imaging showed severe ischemia after bottleneck stenting covering over 50% of the left ventricle in the proximal LAD model. Complete coronary occlusion was necessary for significant collateral growth, which mostly had occurred already during the first wk after the stent occlusion. Dynamic and competitive collateral growth patterns were observed. EF declined from 64 to 41% in the LCX model and to 44% in the LAD model 4 wk after stenting with 12 and 21% infarcted left ventricle in the LCX and LAD models, respectively. The mortality was 32 and 37% in the LCX and LAD models but very (71%) high in the two-vessel disease model. The implantation of a novel bottleneck stent in the proximal LAD or LCX is a novel porcine model of reversible myocardial ischemia (open stent) and ischemic heart failure (occluded stent) and is feasible for the development of new therapeutic approaches.

Baculovirus-mediated vascular endothelial growth factor-D(ΔNΔC) gene transfer induces angiogenesis in rabbit skeletal muscle

BACKGROUND

Occluded arteries and ischemic tissues cannot always be treated by angioplasty, stenting or by-pass-surgery. Under such circumstances, viral gene therapy may be useful in inducing increased blood supply to ischemic area. There is evidence of improved blood flow in ischemic skeletal muscle and myocardium in both animal and human studies using adenoviral vascular endothelial growth factor (VEGF) gene therapy. However, the expression is transient and repeated gene transfers with the same vector are inefficient due to immune responses.

METHODS

Different baculoviral vectors pseudotyped with or without vesicular stomatitis virus glycoprotein (VSV-G) and/or carrying woodchuck hepatitis virus post-transcriptional regulatory element (Wpre) were tested both in vitro and in vivo. VEGF-D(ΔNΔC) was used as therapeutic transgene and lacZ as a control. In vivo efficacy was evaluated as capillary enlargement and transgene expression in New Zealand White (NZW) rabbit skeletal muscle.

RESULTS

A statistically significant capillary enlargement was detected 6 days after gene transfer in transduced areas compared to the control gene transfers with baculovirus and adenovirus encoding β-galactosidase (lacZ). Substantially improved gene transfer efficiency was achieved with a modified baculovirus pseudotyped with VSV-G and carrying Wpre. Dose escalation experiments revealed that either too large volume or too many virus particles caused inflammation and necrosis in the target tissue, whereas 10(9) plaque forming units injected in multiple aliquots resulted in transgene expression with only mild immune reactions.

CONCLUSIONS

We show the first evidence of biologically significant baculoviral gene transfer in skeletal muscle of NZW rabbits using VEGF-D(ΔNΔC) as a therapeutic transgene.

Capillary enlargement, not sprouting angiogenesis, determines beneficial therapeutic effects and side effects of angiogenic gene therapy

AIMS

Currently, it is still unclear which mechanisms drive metabolic benefits after angiogenic gene therapy. The side-effect profile of efficient angiogenic gene therapy is also currently incompletely understood. In this study, the effects of increasing doses of adenoviral (Ad) vascular endothelial growth factor-A (VEGF-A) were evaluated on vascular growth, metabolic benefits, and systemic side effects.

METHODS AND RESULTS

Adenoviral vascular endothelial growth factor-A or AdLacZ control was injected intramuscularly (10(9)-10(11) vp/mL) or intra-arterially (5 × 10(11) vp/mL) into rabbit (n = 102) hindlimb muscles and examined 6 or 14 days later. Blood flow, tissue oedema, metabolic benefits, and the structure of angiogenic vessels were assessed using ultrasound imaging, modified Miles assay, arterial blood gas and metabolite analyses, and light and confocal microscopy, respectively. Safety analyses included cardiac ultrasound, electrocardiograms, and blood and tissue samples. Sprouting angiogenesis was already induced with low AdVEGF-A concentrations, whereas higher concentrations were needed to reach efficient capillary enlargement and increases in target muscle perfusion. Interestingly, metabolic benefits, such as improved aerobic energy metabolism and decreased metabolic acidosis during exercise, after AdVEGF-A administration were highly correlated to the level of capillary enlargement but not to sprouting angiogenesis. Several systemic dose-dependent side effects, including transient increases in liver, kidney, and pancreatic enzymes, and signs of cardiac effects were observed.

CONCLUSION

Efficient capillary enlargement leading to significant increases in tissue perfusion is needed to gain metabolic benefits after angiogenic gene therapy. However, the risk of systemic side effects can increase as the efficiency of angiogenic gene therapy is improved. Importantly, the unstable wall structure of the newly formed vessels seems not to compromise the metabolic benefits.

The effects of VEGF-R1 and VEGF-R2 ligands on angiogenic responses and left ventricular function in mice

AIMS

Vascular endothelial growth factors (VEGFs) and their receptors (VEGF-Rs) are among the most powerful factors regulating vascular growth. However, it has remained unknown whether stimulation of VEGF-R1, VEGF-R2 or both of the receptors produces the best angiogenic responses in myocardium. The aim of this study was to compare the VEGF-R1-specific ligand VEGF-B(186), VEGF-R2-specific ligand VEGF-E and VEGF-A(165,) which stimulates both receptors, regarding their effects on angiogenesis and left ventricular function in mice.

METHODS AND RESULTS

High-resolution echocardiography was used to guide the closed-chest injections of adenoviral (Ad) vectors expressing VEGF-B(186,) VEGF-E, and VEGF-A(165) into the anterior wall of the left ventricle in C57Bl/6J mice. Angiogenic and functional effects were analysed using histology, ultrasound and perfusion analyses 6 (D6) and 14 (D14) days after the Ad injection. AdVEGF-A(165) induced a strong angiogenic response seen as an enlargement of myocardial capillaries whereas angiogenesis induced by AdVEGF-B(186) and AdVEGF-E seemed more physiological. The increase in the capillary area was accompanied with an increase in myocardial perfusion at D6 after the gene injection. AdVEGF-A(165) and AdVEGF-E induced endothelial-specific proliferation whereas AdVEGF-B(186) mostly induced proliferation of cardiomyocytes. AdVEGF-A(165) induced more pronounced tissue damage than AdVEGF-B(186) and AdVEGF-E. Left ventricular function measured as ejection fraction did not change during the follow-up. AdVEGF-A(165) increased both VEGF-R1 and VEGF-R2 protein expression whereas AdVEGF-B(186) and AdVEGF-E did not affect endogenous receptor expression levels.

CONCLUSION

AdVEGF-B(186) and AdVEGF-E are equally potent in inducing therapeutic angiogenesis in mouse myocardium and produce less side effects than AdVEGF-A(165).

Vascular endothelial growth factor-B induces myocardium-specific angiogenesis and arteriogenesis via vascular endothelial growth factor receptor-1- and neuropilin receptor-1-dependent mechanisms

BACKGROUND

New revascularization therapies are urgently needed for patients with severe coronary heart disease who lack conventional treatment options.

METHODS AND RESULTS

We describe a new proangiogenic approach for these no-option patients using adenoviral (Ad) intramyocardial vascular endothelial growth factor (VEGF)-B186 gene transfer, which induces myocardium-specific angiogenesis and arteriogenesis in pigs and rabbits. After acute infarction, AdVEGF-B186 increased blood vessel area, perfusion, ejection fraction, and collateral artery formation and induced changes toward an ischemia-resistant myocardial phenotype. Soluble VEGF receptor-1 and soluble neuropilin receptor-1 reduced the effects of AdVEGF-B186, whereas neither soluble VEGF receptor-2 nor inhibition of nitric oxide production had this result. The effects of AdVEGF-B186 involved activation of neuropilin receptor-1, which is highly expressed in the myocardium, via recruitment of G-protein-alpha interacting protein, terminus C (GIPC) and upregulation of G-protein-alpha interacting protein. AdVEGF-B186 also induced an antiapoptotic gene expression profile in cardiomyocytes and had metabolic effects by inducing expression of fatty acid transport protein-4 and lipid and glycogen accumulation in the myocardium.

CONCLUSIONS

VEGF-B186 displayed strikingly distinct effects compared with other VEGFs. These effects may be mediated at least in part via a G-protein signaling pathway. Tissue-specificity, high efficiency in ischemic myocardium, and induction of arteriogenesis and antiapoptotic and metabolic effects make AdVEGF-B186 a promising candidate for the treatment of myocardial ischemia.

Vascular endothelial growth factor-A and platelet-derived growth factor-B combination gene therapy prolongs angiogenic effects via recruitment of interstitial mononuclear cells and paracrine effects rather than improved pericyte coverage of angiogenic vessels

Vessel stabilization and the inhibition of side effects such as tissue edema are essential in angiogenic gene therapy. Thus, combination gene transfers stimulating both endothelial cell and pericyte proliferation have become of interest. However, there is currently little data to support combination gene transfer in large animal models. In this study, we evaluated the potential advantages of such a strategy by combining the transfer of adenoviral (Ad) vascular endothelial growth factor (VEGF)-A and platelet-derived growth factor (PDGF)-B into rabbit hindlimb skeletal muscle. AdLacZ alone or in combination with AdVEGF-A were used as controls. Contrast-enhanced ultrasound, modified Miles assay, and immunohistology were used to quantify perfusion, vascular permeability, and capillary size, respectively. Confocal microscopy was used in the assessment of pericyte-coverage. The transfer of AdPDGF-B alone and in combination with AdVEGF-A induced prominent proliferation of alpha-smooth muscle actin-, CD31-, RAM11-, HAM56-, and VEGF- positive cells. Although, pericyte recruitment to angiogenic vessels was not improved, combination gene transfer induced a longer-lasting increase in perfusion in both intact and ischemic muscles than AdVEGF-A gene transfer alone. In conclusion, intramuscular delivery of AdVEGF-A and AdPDGF-B, combined, resulted in a prolonged angiogenic response. However, the effects were most likely mediated via paracrine mechanisms rather than an increase in vascular pericyte coverage.

Current Status of Cardiovascular Gene Therapy

Gene transfer for the therapeutic modulation of cardiovascular diseases is an expanding area of gene therapy. During the last decade several approaches have been designed for the treatment of hyperlipidemias, post-angioplasty restenosis, hypertension, and heart failure, and for protection of vascular by-pass grafts and promotion of therapeutic angiogenesis. Adenoviruses (Ads) and adeno-associated viruses (AAVs) are currently the most efficient vectors for delivering therapeutic genes into the cardiovascular system. Gene transfer using local gene delivery techniques have been shown to be superior to less-targeted intra-arterial or intra-venous applications. To date, no gene therapy drugs have been approved for clinical use in cardiovascular applications. In preclinical studies of therapeutic angiogenesis, various growth factors such as vascular endothelial growth factors (VEGFs) and fibroblast growth factors (FGFs), have shown positive results. Gene therapy also appears to have potential clinical applications in improving the patency of vascular grafts and in treating heart failure. Post-angioplasty restenosis, hypertension, and hyperlipidemias (excluding homozygotic familial hypercholesterolemia) can usually be managed satisfactorily by conventional approaches, and are therefore less favored areas for gene therapy. The development of technologies that can ensure long-term, targeted, and regulated gene transfer, and a careful selection of target patient populations, will be very important for the progress of cardiovascular gene therapy in clinical applications.

Adenovirus-Mediated Gene Transfer of Human Vascular Endothelial Growth Factor-D Induces Transient Angiogenic Effects in Mouse Hind Limb Muscle

We evaluated the therapeutic potential of adenovirus (Ad)-mediated human vascular endothelial growth factor-D (hVEGF-D) gene delivery in mice. Hind limbs of hypercholesterolemic mice ( n = 120) were injected with AdhVEGF-D, AdhVEGF-A, control AdLacZ (all at 1x10(11)viral particles) or saline. Animals were killed at 4, 7, 14, 28, and 42 days. Newly formed vessels were characterized for their quantity, sprouting, angiogenic versus lymphangiogenic phenotype, and arterial versus venous phenotype by endothelial enzymes markers, pericyte coverage, and electron microscopy. Perfusion was measured by power Doppler ultrasound and edema by magnetic resonance imaging (MRI). AdhVEGF-D induced significant formation of new blood vessels, which featured lumenal enlargement, branching, and sprouting. Branching originated mainly from arterioles. The highest vessel density was present on days 4-7 and the effect lasted up to 28 days. Endothelial marker enzyme activity indicated the predominance of arterial capillaries and arterioles. Forty percent of the neovessels were positive for desmin, indicating that VEGF-D increased pericyte coverage. However, branching vessels were highly positive for smooth muscle actin pericyte marker but negative for desmin. Maximal perfusion was measured during the first week after AdhVEGF-D gene transfer. Ultrastructural analysis showed endothelial cells enriched with vesiculo-vacuolar organelles and cytoplasmic protrusions. Modest lymphangiogenic activity was also detected, which could contribute to the relatively low level of edema detected by MRI. In conclusions, AdhVEGF-D has a strong angiogenic effect and a modest lymphangiogenic effect in mouse skeletal muscle. VEGF-D also increases the presence of pericytes/smooth muscle cells in neovessels. AdhVEGF-D is a potential new agent for the induction of therapeutic vascular growth in skeletal muscle.