Ali Aydin

Shock efficacy of subcutaneous implantable cardioverter-defibrillator for prevention of sudden cardiac death: initial multicenter experience.

Background—Recently, subcutaneous implantable cardioverter-defibrillator (S-ICD) has become available. The aim of our study was to assess the efficacy of S-ICD in a clinical setting. Methods and Results—Between June 2010 and July 2011, 40 consecutive patients (42±15 years; body mass index, 27±6 kg/m2; left ventricular ejection fraction, 47±15%; 28 men) received an S-ICD for primary (n=17) or secondary prevention (n=23 [58%]) at 3 institutions in Germany. Intraoperative defibrillation efficacy testing failed in 1 patient with severely reduced left ventricular ejection fraction; testing was effective in all other patients. All episodes stored in the S-ICD were analyzed for appropriate and inappropriate detection, as well as effective shock delivery to convert ventricular tachyarrhythmia into sinus rhythm. During a median follow-up of 229 (interquartile range, 116–305) days, 4 patients experienced 21 episodes, with correct detection of ventricular tachyarrhythmia and subsequent shock therapy. A total of 28 shocks were delivered in these 4 patients. Mixed logistic regression modeling revealed a shock efficacy of 96.4% (95% CI, 12.8%–100%). The efficacy of first shocks, however, was only 57.9% (95% CI, 35.6%–77.4%). Four episodes were incorrectly classified as ventricular tachyarrhythmia, which led to inappropriate shock delivery in 2 patients. Conclusions—Ineffective shock delivery may occur in patients with S-ICD, even after successful intraoperative testing. Multicenter trials are required with close monitoring of safety and efficacy end points to identify patients who may be at risk for shock failure.

Prospective risk stratification of sudden cardiac death in Marfan's syndrome

BACKGROUND Marfan syndrome (MFS) is a variable, autosomal-dominant disorder of the connective tissue. In MFS serious ventricular arrhythmias and sudden cardiac death (SCD) can occur. The aim of this prospective study was to reveal underlying risk factors and to prospectively investigate the association between MFS and SCD in a long-term follow-up. METHODS 77 patients with MFS were included. At baseline serum N-terminal pro-brain natriuretic peptide (NT-proBNP), transthoracic echocardiogram, 12-lead resting ECG, signal-averaged ECG (SAECG) and a 24-h Holter ECG with time- and frequency domain analyses were performed. The primary composite endpoint was defined as SCD, ventricular tachycardia (VT), ventricular fibrillation (VF) or arrhythmogenic syncope. RESULTS The median follow-up (FU) time was 868 days. Among all risk stratification parameters, NT-proBNP remained the exclusive predictor (hazard ratio [HR]: 2.34, 95% confidence interval [CI]: 1.1 to 4.62, p=0.01) for the composite endpoint. With an optimal cut-off point at 214.3 pg/ml NT-proBNP predicted the composite primary endpoint accurately (AUC 0.936, p=0.00046, sensitivity 100%, specificity 79.0%). During FU, seven patients of Group 2 (NT-proBNP ≥ 214.3 pg/ml) reached the composite endpoint and 2 of these patients died due to SCD. In five patients, sustained VT was documented. All patients with a NT-proBNP<214.3 pg/ml (Group 1) experienced no events. Group 2 patients had a significantly higher risk of experiencing the composite endpoint (logrank-test, p<0.001). CONCLUSIONS In contrast to non-invasive electrocardiographic parameter, NT-proBNP independently predicts adverse arrhythmogenic events in patients with MFS.

Observational Cohort Study of Ventricular Arrhythmia in Adults with Marfan Syndrome Caused by FBN1 Mutations

Background Marfan syndrome is associated with ventricular arrhythmia but risk factors including FBN1 mutation characteristics require elucidation. Methods and Results We performed an observational cohort study of 80 consecutive adults (30 men, 50 women aged 42±15 years) with Marfan syndrome caused by FBN1 mutations. We assessed ventricular arrhythmia on baseline ambulatory electrocardiography as >10 premature ventricular complexes per hour (>10 PVC/h), as ventricular couplets (Couplet), or as non-sustained ventricular tachycardia (nsVT), and during 31±18 months of follow-up as ventricular tachycardia (VT) events (VTE) such as sudden cardiac death (SCD), and sustained ventricular tachycardia (sVT). We identified >10 PVC/h in 28 (35%), Couplet/nsVT in 32 (40%), and VTE in 6 patients (8%), including 3 with SCD (4%). PVC>10/h, Couplet/nsVT, and VTE exhibited increased N-terminal pro–brain natriuretic peptide serum levels(P<.001). All arrhythmias related to increased NT-proBNP (P<.001), where PVC>10/h and Couplet/nsVT also related to increased indexed end-systolic LV diameters (P = .024 and P = .020), to moderate mitral valve regurgitation (P = .018 and P = .003), and to prolonged QTc intervals (P = .001 and P = .006), respectively. Moreover, VTE related to mutations in exons 24–32 (P = .021). Kaplan–Meier analysis corroborated an association of VTE with increased NT-proBNP (P<.001) and with mutations in exons 24–32 (P<.001). Conclusions Marfan syndrome with causative FBN1 mutations is associated with an increased risk for arrhythmia, and affected persons may require life-long monitoring. Ventricular arrhythmia on electrocardiography, signs of myocardial dysfunction and mutations in exons 24–32 may be risk factors of VTE.

Ascending aortic aneurysm and aortic valve dysfunction in bicuspid aortic valve disease

BACKGROUND The relationship of aortic valve dysfunction and ascending aortic aneurysm is unclear in adults with bicuspid aortic valve disease. METHODS We retrospectively studied 134 consecutive out-patients (98 men, 36 women aged 43 ± 18 years) with bicuspid aortic valve disease. To investigate the relationship of ascending aortic aneurysm and aortic valve dysfunction we exclusively considered severe pathologies that required treatment by surgical or percutaneous intervention. RESULTS Of 134 patients, 39 had aortic valve dysfunction without concomitant ascending aortic aneurysm which had been treated previously with isolated valve surgery or percutaneous valvuloplasty comprising 25 patients with aortic stenosis (19%) and 14 patients with aortic regurgitation (10%). Conversely, 26 patients had ascending aortic aneurysm which had been treated previously with aortic surgery (19%). Of these, ascending aortic aneurysm was associated with severe aortic stenosis in 13 patients and with severe aortic regurgitation in 7 patients, whereas aneurysm was unrelated to severe aortic valve dysfunction in the remaining 6 patients including 2 without any degree of aortic valve dysfunction. The maximal aortic diameters were similar at the time of aortic surgery irrespective of presence of severe aortic valve dysfunction (P=.527). Other characteristics of patients with ascending aortic aneurysm were also similar irrespective of presence or type of aortic valve dysfunction. CONCLUSION The majority of patients with bicuspid aortic valve disease exhibit ascending aortic aneurysm in conjunction with severe aortic valve dysfunction. However, in our study 6 of 134 (5%) of persons with bicuspid aortic valve disease developed ascending aortic aneurysm without aortic valve dysfunction.

Central pulse pressure and augmentation index in asymptomatic bicuspid aortic valve disease

a Centre of Cardiology and Cardiovascular Surgery, University Hospital Eppendorf, Hamburg, Germany b Department of Medical Biometry and Epidemiology, University Hospital Eppendorf, Hamburg, Germany c Medical Clinic II, University of Lubeck, Germany d Institute of Epidemiology and Social Medicine, University of Muenster, Germany e Helmholtz Zentrum Munchen, German Research Center for Environmental Health (GmbH), Institute of Epidemiology II, Neuherberg, Germany f Institute of Medical Genetics, Charite Universitatsmedizin Berlin, Germany

Aortic aneurysms after correction of aortic coarctation: a systematic review.

Despite advanced techniques for surgical or percutaneous therapy coarctation of the aorta continues to carry a high risk of aneurysmal formation. Mortality of these aneurysms ranges between <1 and >90%, reflecting remarkable differences in surgical strategies and the follow-up management of coarctation. We review the frequency, anatomical types, risk factors and mechanisms of aortic aneurysm forming late after surgical or percutaneous therapy of aortic coarctation. We emphasize that aneurysms do not form exclusively at the site of previous intervention, but also at remote locations such as the ascending aorta. Moreover, aneurysm formation may only in part be attributed to a specific technique of coarctation therapy, and we emphasize the role of a bicuspid aortic valve and inherent weakness of the aortic wall as significant risk factors for aneurysm after aortic coarctation. We report the presenting symptoms, follow-up protocols, and imaging criteria for local and proximal aneurysms. Finally, we discuss criteria for prophylactic intervention at the site of such aneurysms, and present therapeutic options for different types of aneurysms. With this systematic review, we wish to provide data for establishing more uniform strategies for preventing, diagnosing and treating aneurysms associated with aortic coarctation.

Necessity of epicardial ablation for ventricular tachycardia after sequential endocardial approach

BACKGROUND Catheter ablation (CA) of ventricular tachycardia (VT) is an important treatment option in patients with structural heart disease (SHD) and implantable cardioverter defibrillator (ICD). A subset of patients requires epicardial CA for VT. OBJECTIVE The purpose of the study was to assess the significance of epicardial CA in these patients after a systematic sequential endocardial approach. METHODS Between January 2009 and October 2012 CA for VT was analyzed. A sequential CA approach guided by earliest ventricular activation, pacemap, entrainment and stimulus to QRS-interval analysis was used. Acute CA success was assessed by programmed ventricular stimulation. ICD interrogation and 24h-Holter ECG were used to evaluate long-term success. RESULTS One hundred sixty VT ablation procedures in 126 consecutive patients (114 men; age 65±12years) were performed. Endocardial CA succeeded in 250 (94%) out of 265 treated VT. For 15 (6%) VT an additional epicardial CA was performed and succeeded in 9 of these 15 VT. Long-term FU (25±18.2month) showed freedom of VT in 104 pts (82%) after 1.2±0.5 procedures, 11 (9%) suffered from repeated ICD shocks and 11 (9%) died due to worsening of heart failure. CONCLUSIONS Despite a heterogenic substrate for VT in SHD, endocardial CA alone results in high acute success rates. In this study additional epicardial CA following a sequential endocardial mapping and CA approach was performed in 6% of VT. Thus, due to possible complications epicardial CA should only be considered if endocardial CA fails.

Coronary Sinus Lead Removal: A Comparison between Active and Passive Fixation Leads

Background Implantation of coronary sinus (CS) leads may be a difficult procedure due to different vein anatomies and a possible lead dislodgement. The mode of CS lead fixation has changed and developed in recent years. Objectives We compared the removal procedures of active and passive fixation leads. Methods Between January 2009 and January 2014, 22 patients at our centre underwent CS lead removal, 6 active and 16 passive fixation leads were attempted using simple traction or lead locking devices with or without laser extraction sheaths. Data on procedural variables and success rates were collected and retrospectively analyzed. Results The mean patient age was 67.2 ± 9.8 years, and 90.9% were male. The indication for lead removal was infection in all cases. All active fixation leads were Medtronic® Attain StarFix™ Model 4195 (Medtronic Inc., Minneapolis, MN, USA). The mean time from implantation for the active and passive fixation leads was 9.9 ± 11.7 months (range 1.0–30.1) and 48.7 ± 33.6 months (range 5.7–106.4), respectively (p = 0.012). Only 3 of 6 StarFix leads were successfully removed (50%) compared to 16 of 16 (100%) of the passive fixation CS leads (p = 0.013). No death or complications occurred during the 30-day follow-up. Conclusion According to our experience, removal of the Starfix active fixation CS leads had a higher procedural failure rate compared to passive.

Orthostatic Blood Pressure Test for Risk Stratification in Patients with Hypertrophic Cardiomyopathy

Background Hypertrophic cardiomyopathy (HCM) is the most common cause of sudden cardiac death (SCD) in young adults, mainly ascribed to ventricular tachycardia (VT). Assuming that VT is the major cause of (pre-) syncope in HCM patients, its occurrence is essential for SCD risk stratification and primarily preventive ICD-implantation. However, evidence of VT during syncope is often missing. As the differentiation of potential lethal causes for syncope such as VT from more harmless reasons is crucial, HCM patients were screened for orthostatic dysregulation by using a simple orthostatic blood pressure test. Methods Over 15 months (IQR [9;20]) 100 HCM patients (55.8±16.2 yrs, 61% male) were evaluated for (pre-)syncope and VT (24h-ECGs, device-memories) within the last five years. Eighty patients underwent an orthostatic blood pressure test. Logistic regression models were used for statistical analysis. Results In older patients (>40 yrs) a positive orthostatic test result increased the chance of (pre-) syncope by a factor of 63 (95%-CI [8.8; 447.9], p<0.001; 93% sensitivity, 95%-CI [76; 99]; 74% specificity, 95%-CI [58; 86]). No correlation with VT was shown. A prolonged QTc interval also increased the chance of (pre-) syncope by a factor of 6.6 (95%-CI [2.0; 21.7]; p=0.002). Conclusions The orthostatic blood pressure test is highly valuable for evaluation of syncope and presyncope especially in older HCM patients, suggesting that orthostatic syncope might be more relevant than previously assumed. Considering the high complication rates due to ICD therapies, this test may provide useful information for the evaluation of syncope in individual risk stratification and may help to prevent unnecessary device implantations, especially in older HCM patients.

Shock Efficacy of the Subcutaneous ICD for Prevention of Sudden Cardiac Death: Initial Multicenter Experience

Background—Recently, subcutaneous implantable cardioverter-defibrillator (S-ICD) has become available. The aim of our study was to assess the efficacy of S-ICD in a clinical setting. Methods and Results—Between June 2010 and July 2011, 40 consecutive patients (42±15 years; body mass index, 27±6 kg/m2; left ventricular ejection fraction, 47±15%; 28 men) received an S-ICD for primary (n=17) or secondary prevention (n=23 [58%]) at 3 institutions in Germany. Intraoperative defibrillation efficacy testing failed in 1 patient with severely reduced left ventricular ejection fraction; testing was effective in all other patients. All episodes stored in the S-ICD were analyzed for appropriate and inappropriate detection, as well as effective shock delivery to convert ventricular tachyarrhythmia into sinus rhythm. During a median follow-up of 229 (interquartile range, 116–305) days, 4 patients experienced 21 episodes, with correct detection of ventricular tachyarrhythmia and subsequent shock therapy. A total of 28 shocks were delivered in these 4 patients. Mixed logistic regression modeling revealed a shock efficacy of 96.4% (95% CI, 12.8%–100%). The efficacy of first shocks, however, was only 57.9% (95% CI, 35.6%–77.4%). Four episodes were incorrectly classified as ventricular tachyarrhythmia, which led to inappropriate shock delivery in 2 patients. Conclusions—Ineffective shock delivery may occur in patients with S-ICD, even after successful intraoperative testing. Multicenter trials are required with close monitoring of safety and efficacy end points to identify patients who may be at risk for shock failure.