Stephan Hohmann

Risk for ventricular fibrillation in peripartum cardiomyopathy with severely reduced left ventricular function—value of the wearable cardioverter/defibrillator

The true incidence of life‐threatening ventricular tachyarrhythmic events and the risk of sudden cardiac death in the early stage of peripartum cardiomyopathy (PPCM) are still unknown. We aimed to assess the usefulness of the wearable cardioverter/defibrillator (WCD) to bridge a potential risk for life‐threatening arrhythmic events in patients with early PPCM, severely reduced left ventricular ejection fraction (LVEF) and symptoms of heart failure.

Avoiding Untimely Implantable Cardioverter/Defibrillator Implantation by Intensified Heart Failure Therapy Optimization Supported by the Wearable Cardioverter/Defibrillator-The PROLONG Study.

Background Optimal timing of implantation of an implantable cardioverter/defibrillator (ICD) after newly diagnosed heart failure is unclear given that late reverse remodelling may occur. We aimed to analyze left ventricular ejection fraction (LVEF) after diagnosis of an LVEF ≤35% during optimization of heart failure drug therapy. Methods and Results One hundred fifty‐six patients with newly diagnosed LVEF ≤35% receiving a wearable cardioverter/defibrillator (WCD) were analyzed. WCD was prescribed for 3 months until first re‐evaluation. Indications for prolongation of WCD wearing period instead of ICD implantation were: (1) LVEF at 3‐month visit 30% to 35%; (2) increase in LVEF of ≥5% compared to the last visit; and (3) nonoptimized heart failure medication. Mean LVEF was 24±7% at diagnosis and 39±11% at last follow‐up (mean, 12±10 months). Whereas 88 patients presented a primary preventive ICD indication (LVEF ≤35%) at 3‐month follow‐up, only 58 showed a persistent primary preventive ICD indication at last follow‐up. This delayed improvement in LVEF was related to nonischemic origin of cardiomyopathy, New York Heart Association functional class at baseline, heart rate, better LVEF after 3 months, and higher dosages of mineralocorticoid receptor antagonist. Twelve appropriate WCD shocks for ventricular tachycardia/ventricular fibrillation occurred in 11 patients. Two patients suffered from ventricular tachycardia/ventricular fibrillation beyond 3 months after diagnosis. Conclusions A relevant proportion of patients with newly diagnosed heart failure shows recovery of LVEF >35% beyond 3 months after initiation of heart failure therapy. To avoid untimely ICD implantation, prolongation of WCD period should be considered in these patients to prevent sudden cardiac death while allowing left ventricular reverse remodeling during intensified drug therapy.

Subcutaneous Implantable Cardioverter-Defibrillator Shocks After Left Ventricular Assist Device Implantation

A 42-year-old man experiencing nonischemic cardiomyopathy with severely reduced left ventricular function and advanced heart failure met the criteria for primary prophylactic implantation of an implantable cardioverter-defibrillator (ICD). A subcutaneous ICD (S-ICD; EMBLEM; Boston Scientific, Marlborough, MA) was implanted at a secondary center in November 2015 with the lead (3401; Boston Scientific) tunnelled in left parasternal position. Before implantation, surface ECG screening was performed following the manufacturer’s instructions. A few weeks later, the patient was transferred to Hannover Medical School because of heart failure deterioration (New York Heart Association class IV). After careful evaluation, a continuous-flow left ventricular assist device (LVAD; HeartMate 3; Thoratec, Pleasanton, CA) was implanted using conventional sternotomy.1 Approximately 1 hour after LVAD implantation, the patient received 31 S-ICD shocks. The device was immediately deactivated. Interrogation of the S-ICD revealed normal sinus rhythm during the shocks. However, R waves were diminished and superimposed by electric …

Ventricular arrhythmias in patients with newly diagnosed nonischemic cardiomyopathy: Insights from the PROLONG study: Ventricular arrhythmias in newly diagnosed non-ischemic cardiomyopathy

Patients with nonischemic cardiomyopathy (NICM) reportedly have low incidence of appropriate shocks from wearable cardioverter‐defibrillators (WCDs). A recent study questions the benefit from primary preventive implantation of implantable cardioverter‐defibrillators in NICM. We therefore analyzed a subgroup of patients with NICM from the PROLONG study.

Systematic ajmaline challenge in patients with long QT 3 syndrome caused by the most common mutation: a multicentre study.

Aims Overlap syndromes of long QT 3 syndrome (LQT3) and the Brugada syndrome (BrS) have been reported. Identification of patients with an overlapping phenotype is crucial before initiation of Class I antiarrhythmic drugs for LQT3. Aim of the present study was to elucidate the yield of ajmaline challenge in unmasking the Brugada phenotype in patients with LQT3 caused by the most common mutation, SCN5A-E1784K. Methods and results Consecutive families in tertiary referral centres diagnosed with LQT3 caused by SCN5A-E1784K were included in the study. Besides routine clinical work-up, ajmaline challenge was performed after informed consent. A total of 23 subjects (11 female, mean age 27 ± 14 years) from 4 unrelated families with a family history of sudden cardiac death and familial diagnosis of the SCN5A-E1784K mutation underwent ajmaline challenge and genetic testing. Sixteen subjects (9 female) were found to be heterozygous carriers of SCN5A-E1784K. Ajmaline challenge was positive in 12 out of the 16 (75%) mutation carriers, but negative in all non-carriers. Following ajmaline, a significant shortening of the rate-corrected JT (JTc) interval was observed in mutation carriers. The baseline JTc interval was significantly longer in mutation carriers with a positive ajmaline challenge compared with those with a negative one. Conclusion Overlap of LQT3 and BrS in patients carrying the most common mutation is high. Therefore, ajmaline challenge represents an important step to rule out potential BrS overlap in these patients before starting sodium channel blockers for the beneficial effect of QT shortening in LQT3.

Primary and secondary prophylactic ICD therapy in congenital electrical and structural cardiomyopathies

Congenital electrical and structural cardiomyopathies are rare and associated with an increased risk for syncope and sudden cardiac death in the young. Due to the young age of the patients and the limited data available, risk stratification and especially ICD therapy are challenging. In this young patient collective, ICD therapy is associated with a high complication rate, which does not justify unreserved primary prophylactic ICD implantation. The aim of this review is to elucidate risk stratification and ICD therapy of various electrical and structural cardiomyopathies.

Implantable cardioverter defibrillator therapy in grown-up patients with transposition of the great arteries—role of anti-tachycardia pacing

Background Grown-up patients with surgically corrected dextro-transposition of the great arteries (dTGA) as well as patients with congenitally corrected transposition of the great arteries (ccTGA) carry a high risk of ventricular arrhythmias. Data regarding implantable cardioverter defibrillator (ICD) therapy and efficacy of anti-tachycardia pacing in these patients is limited. Methods Clinical data from a contemporary cohort of ICD carriers with atrial switch-corrected dTGA and burdened right ventricle or with ccTGA were obtained retrospectively from hospital records and patients were followed for additional 25 months prospectively. Clinical characteristics and ICD episode data were analyzed. Results Fourteen ICD carriers (8 male) with dTGA or ccTGA were included in the analysis. Four patients received the ICD for primary prevention based on severely reduced systemic ventricular function. The remaining patients had an ICD indication for secondary prevention. Cumulative follow-up added up to 113.5 patient-years. One patient died suddenly due to massive pulmonary embolism. One patient received a ventricular assist device. There were no arrhythmic deaths during the prospective follow-up period. Nine patients (64%) experienced a total of 177 ventricular tachyarrhythmias. Anti-tachycardia pacing was highly effective with 80% success rate in termination of arrhythmias. Five patients (36%) suffered from a total of 28 inappropriate ICD shocks for supraventricular tachycardia. Conclusions In a contemporary cohort of ICD carriers with dTGA and ccTGA we observed a high proportion of appropriate ICD therapies for ventricular tachyarrhythmias. Over a period of up to 15 years almost two thirds of the patients received appropriate therapies. ATP was highly effective in our cohort and should therefore be programmed whenever possible.

ICD-Therapie zur Primär- und Sekundärprophylaxe kongenitaler arrhythmogener Erkrankungen@@@Primary and secondary prophylactic ICD therapy in congenital electrical and structural cardiomyopathies

Congenital electrical and structural cardiomyopathies are rare and associated with an increased risk for syncope and sudden cardiac death in the young. Due to the young age of the patients and the limited data available, risk stratification and especially ICD therapy are challenging. In this young patient collective, ICD therapy is associated with a high complication rate, which does not justify unreserved primary prophylactic ICD implantation. The aim of this review is to elucidate risk stratification and ICD therapy of various electrical and structural cardiomyopathies.