Initial experience with telemonitoring in left ventricular assist device patients.

BACKGROUND: Left ventricular assist devices (LVAD) are increasingly used in patients with end stage heart failure. The HeartAssist 5 and aVAD LVADs offer telemetric monitoring capabilities. Here we report our initial single centre experience with the largest telemonitoring cohort of LVAD patients. METHODS: Eleven patients (9 males) received a telemonitoring-capable LVAD and were included in our telemonitoring cohort. Waveforms and alarm data were obtained from the telemonitoring system and hospital records were reviewed for clinical data. RESULTS: Mean age at LVAD implantation was 59±5.1 years (mean ± standard deviation). Seven patients had non-ischemic cardiomyopathy and 4 patients had ischemic cardiomyopathy. Median LVEF at implant was 16% (IQR, 15-20%). The total follow-up time was 2,438 patient-days. A total of 6,216 alarm messages were generated in 11 patients. Most common were low flow alarms due to hypovolemia, followed by low flow alarms because of suspected pump thrombosis. One patient died during follow-up, one received a cardiac transplant and one had the LVAD explanted because of pump thrombosis. Pump thrombosis was suspected in 5 patients with 8 episodes of sudden flow decreases and laboratory signs of haemolysis. CONCLUSIONS: Real-time telemonitoring of LVAD pump flow, motor speed and power consumption is a promising tool in the follow-up of LVAD recipients. Trending pump flow over hours or days can assist in the early detection of complications, especially flow reductions due to hypovolemia and LVAD thrombosis. Further studies are warranted to delineate the impact of remote monitoring on patients' prognosis.

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.

[Syncopes and channelopathies]. / Synkopen und Ionenkanalerkrankungen.

Syncope can be the first manifestation of cardiac channelopathies, namely Brugada syndrome, long QT syndrome, short QT syndrome and catecholaminergic polymorphic ventricular tachycardia (CPVT). Patients affected by these rare diseases are at increased risk for sudden cardiac death due to ventricular tachyarrhythmias and require specific therapy and follow-up. As syncope is common in the general population, only few cases are caused by an underlying channelopathy. Nevertheless, the diagnosis should be considered in young patients with structurally normal hearts, especially if the history of syncope is typical for an arrhythmogenic cause, in the presence of characteristic echocardiogram (ECG) patterns, and if there is a family history of channelopathies or sudden cardiac death. On the other hand, syncope plays an important role in the management of patients with diagnosed channelopathies, as they may indicate an increased risk for sudden cardiac death. The predictive value and consequences for treatment vary between the different channelopathies. However, data on this issue are scarce due to the low prevalence of these diseases. This review highlights typical findings in the medical history and diagnostic tests that may point towards an underlying channelopathy in patients with syncope. It also discusses the prognostic and therapeutic implications of a history of syncope in patients with known channelopathies.

One symptom, two arrhythmias: the rare and the even rarer.

BACKGROUND: Wolff-Parkinson-White (WPW) syndrome and idiopathic left ventricular tachycardia (ILVT) are rare and up to now the coexistence of both entities has rarely been reported. In patients with ventricular preexcitation the underlying mechanism of paroxysmal tachycardia most likely is atrioventricular reentrant tachycardia (AVRT). However, without ECG documentation of the tachycardia diagnosis of the underlying mechanism cannot be made due to similar clinical presentation of AVRT and ILVT. CASE PRESENTATION: We report a case of a two-staged occurrence of two rare arrhythmias in a young adult, who was admitted to our hospital twice within 6 months because of paroxysmal tachycardia. WPW syndrome and ILVT as underlying arrhythmias have been diagnosed and were ablated successfully. CONCLUSIONS: This case highlights the diagnostic defiance of rare tachycardia entities and the paramount importance of ECG documentation and analysis of all available tachycardia ECGs.

[Device-based remote monitoring : Current evidence]. / Devicebasiertes Telemonitoring : Aktuelle Studienlage.

Telemedicine is increasingly used in clinical cardiology. It offers early detection of arrhythmias, technical device follow-up and support of heart failure management. Regarding technical device follow-up, remote monitoring significantly reduces usage of the health care system. Furthermore, remote monitoring is associated with a significantly reduced time from device malfunction to physician's perception of the event. Using remote monitoring, inappropriate ICD (implantable cardioverter defibrillator) shocks can be significantly reduced compared to routine in-office follow-up. In retrospective studies and meta-analyses a prognostic benefit with respect to mortality has been shown. Device-based detection of atrial fibrillation and atrial high rate episodes is feasible. However, clinical relevance is currently studied in prospective randomized clinical trials. Heart failure management based on surrogate parameters has not been shown to significantly improve outcome. However, therapeutic management based on pulmonary artery pressure has been shown to significantly reduce morbidity and mortality. This review offers a comprehensive overview on the role of remote monitoring in heart failure management, technical device follow-up and detection of atrial fibrillation and atrial high rate episodes.

Electric smog: telemetry interference between ICD and LVAD.

Electromagnetic interferences between implantable cardioverter/defibrillators (ICD) and left ventricular assist devices (LVAD) impacting telemetry have been described in previous generations of ICD as well as LVAD, but have been predominantly overcome in current ICD generations. After introduction of a new fully magnetically levitated centrifugal continuous-flow circulatory pump, we report a case of tenacious telemetry interference between the HeartMate 3 LVAD and an ICD after battery exchange to an Iforia 5. Initialization of the initial telemetry handshake was only possible using several specific maneuvers simultaneously. In order to exclude device-device interference, we suggest to place the ICD above the LVAD before implantation and to test for possible telemetry interferences.

Ventricular arrhythmias in patients with newly diagnosed nonischemic cardiomyopathy: Insights from the PROLONG study.

BACKGROUND: 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. HYPOTHESIS: Patients with newly diagnosed NICM show a risk for ventricular tachyarrhythmia. METHODS: The PROLONG study included 167 patients with newly diagnosed heart failure and left ventricular ejection fraction (LVEF) ≤35% with a WCD. Patients with NICM were identified and included in this analysis. RESULTS: 117 patients presented with NICM. Sixty-five (55%) were male; mean age was 51 ± 15 years. Mean LVEF at diagnosis was 23% ± 7%. Mean follow-up was 11 ± 10 months. Mean WCD wear time was 101 ± 82 days; mean wear time per day was 21.4 ± 4.5 hours. Overall, 12 ventricular arrhythmias occurred in 10 (9%) patients (6 DCM, 4 PPCM). Nine appropriate WCD shocks for hemodynamically unstable ventricular tachycardia/fibrillation in 8 (7%) patients were observed. Two patients presented sustained hemodynamically stable ventricular tachycardia for >30 minutes detected by the WCD, but withheld WCD therapy. CONCLUSIONS: Patients with newly diagnosed NICM and LVEF ≤35% show an elevated risk of ventricular tachycardia/fibrillation during initiation and optimization of heart failure therapy. To prevent sudden cardiac death, WCD should be considered in patients with newly diagnosed NICM with severely reduced LVEF.

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.

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.

The "Pain wave": P­wave oversensing in subcutaneous ICD.

A 46-year old man was implanted with a totally subcutaneous implantable defibrillator, after having a documented episode of cardiac arrest due to idiopathic ventricular fibrillation. During the 4­month follow-up, an episode of inappropriate triple counting due to P­ and T­wave oversensing was detected. Although preoperative screening, high detection rates, and the INSIGHT(TM) discrimination algorithm have reduced the incidence of oversensing-related implantable cardioverter defibrillator (ICD) shocks, continuous evaluation of appropriate sensing vectors at rest, during positional maneuver, and exercise, seems to be mandatory at each follow-up visit.

Cardiac resynchronization therapy improves psycho-cognitive performance in patients with heart failure.

BACKGROUND: Reduced cognitive performance and high prevalence of depression have been reported in patients with congestive heart failure (CHF) and severe left ventricular dysfunction. However, effects of contemporary device therapy on cognitive performance and depression symptoms have not been studied thoroughly. METHODS: Seventy-four consecutive CHF patients-45 receiving a biventricular defibrillator (CRT-D) and 29 receiving an implantable single or dual-chamber defibrillator (ICD) as a control group-were enrolled in this investigator-initiated, prospective, controlled, and investigator-blinded study. A set of neuropsychological tests (mini-mental state examination, DemTect, age-concentration test, and Beck depression inventory) was performed before, at 3 and at 6 months after device implantation. RESULTS: DemTect-score improved significantly (F = 7.8; P = 0.007) after CRT-D-implantation compared with ICD. Age-concentration test revealed better concentration ability after CRT-D-implantation (F = 8.3; P = 0.005) compared with ICD. Under CRT-D mini-mental state examination showed a significant improvement (F = 4.2; P = 0.043). CRT with defibrillator therapy also improved depression revealed by beck depression inventory (F = 14.7; P< 0.001) compared with ICD. CONCLUSION: This prospective study is the first to demonstrate psycho-cognitive improvement by resynchronization therapy in CHF patients with severe left ventricular dysfunction. In contrast to ICD therapy, the beneficial effect of CRT-D on psycho-cognitive performance might be attributed to improved cardiac function and haemodynamics.

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

AIMS: 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. METHODS AND RESULTS: Twelve consecutively admitted women with PPCM were included in this single-centre, prospective observational study between September 2012 and September 2013. Patients with LVEF ≤35% were considered to use the WCD for 3 months or even 6 months when considered necessary for LVEF recovery. Nine of the 12 women had a severely reduced LVEF (mean 18.3%) at the time of study enrollment; seven women received a WCD, while two patients refused to wear a WCD. During a median WCD follow-up of 81 days (range 25-345 days), we observed a total of four events of ventricular fibrillation with appropriate and successful WCD shocks in three of the seven women receiving a WCD. No syncope or sudden arrhythmic deaths occurred in women not using the WCD during a median follow-up of 12 months (range 5-15 months). All women showed impressive improvement of LVEF during follow-up. CONCLUSION: PPCM patients with severely reduced LVEF have an elevated risk for ventricular tachyarrhythmias early after diagnosis. Therefore, use of the WCD should be considered in all women with early-stage PPCM and severely reduced LVEF during the first 6 months after initiation of heart failure therapy.

Clinical relevance of slow ventricular tachycardia in heart failure patients with primary prophylactic implantable cardioverter defibrillator indication.

AIMS: Implantable cardioverter defibrillators (ICDs) have shown to reduce all-cause mortality in heart failure patients. In SCD-HeFT study, ICDs were programmed with a detection zone of ≥ 187 b.p.m. Thus, the incidence and clinical significance of slower ventricular tachycardias (VTs) in these patients remains largely unknown, though clinically important for device selection, programming, and follow-up. METHODS AND RESULTS: We prospectively studied symptomatic heart failure patients with an indication for a primary prophylactic ICD with or without concomitant resynchronization therapy according to SCD-HeFT inclusion criteria. Devices were programmed to an additional monitor zone for slow VTs at heart rates 130-186 b.p.m. Two hundred consecutive patients (86% male) were followed for a mean of 509 ± 308 days. One hundred and thirty-seven patients (68.5%) were New York Heart Association class III, 75 patients (37.5%) were on cardiac resynchronization therapy, and 124 (62%) had ischaemic cardiomyopathy. We observed 473 VT episodes in 36 patients (18%) and 131 ventricular fibrillation episodes in 30 patients (15%). Ventricular tachycardia overall occurred in 40 patients (20%). The incidence of slow VTs was low in only 12 patients (6%). No patient with slow VT suffered from syncope, palpitation, or decompensation leading to hospitalization. We did not find any reliable predictor for increased long-term risk of slow VTs. CONCLUSION: Incidence of slow VTs in a typical heart failure population with primary prophylactic ICD-implantation ± resynchronization therapy is very low. Slow VTs detected in the ICD monitor zone remained clinically asymptomatic. Thus, single chamber and atriobiventricular ICDs with a VT/ventricular fibrillation zone of ≥ 187 b.p.m. and one burst before shock delivery might be sufficient and pragmatic for the vast majority of these patients.

Stable cystatin C serum levels confirm normal renal function in patients with dronedarone-associated increase in serum creatinine.

Dronedarone is a new antiarrhythmic drug for patients with nonpermanent atrial fibrillation (AF). A relatively consistent finding in all trials studying dronedarone was a moderate but significant elevation of serum creatinine. Since dronedarone competes for the same organic cation transporter in the distal renal tubule with creatinine, serum creatinine and its derived estimated glomerular filtration rate might not reflect true renal function in patients on dronedarone. We therefore investigated alternative markers for renal function in these patients. We prospectively included 20 patients with nonpermanent AF in whom dronedarone 400 mg twice daily was started. Patients had normal renal function and serum creatinine; serum cystatin C and creatinine clearance were measured before treatment and 10 and 90 days after treatment started. Mean serum creatinine level for all 20 patients at baseline (day 0) was 84.55 ± 12.14 and 87.8 ± 17.59 µmol/L on day 10. This slight increase in all patients was not significant. Patients were now divided into the predefined groups of "increased creatinine" (increase in serum creatinine level > 1 standard deviation) and "not increased creatinine." Patients with increased creatinine levels (n = 5) showed a significant elevation of serum creatinine levels from day 0 to day 10 (82.4 ± 9.18 to 104.4 ± 12.74 µmol/L; P = .003), whereas change in serum creatinine levels in the not increased creatinine group (n = 15) was not significant. Serum cystatin C levels remained stable in both of these groups (increased creatinine group: 0.76 ± 0.08 to 0.78 ± 0.08 mg/L; P = .65; not increased creatinine group: 0.77 ± 0.108 to 0.77 ± 0.107 mg/L; P = .906). In conclusion, cystatin C represents an easily available and reliable biomarker for estimation of true renal function in patients on dronedarone treatment.

Implantable defibrillator therapy for ventricular tachyarrhythmia in left ventricular assist device patients.

AIMS: Ventricular arrhythmias (VA) occur frequently after permanent left ventricular assist device (LVAD) implantation in end stage heart failure. Left ventricular assist device patients require rhythm control in contrast to patients with biventricular support. However, the rationale for implantable cardioverter-defibrillator (ICD) utilization in LVAD patients remains unclear. This study investigated the safety and efficacy of primary prevention ICD therapy and the rate of appropriate ICD interventions in LVAD patients. METHODS AND RESULTS: We prospectively collected data from patients receiving LVADs. Patients without previous ICD received an ICD after LVAD implantation for primary prevention. Sixty-one patients with LVAD and ICD were followed prospectively for 365 +/- 321 days. Nine patients died from thromboembolism or haemorrhage. Overall, the rate of appropriate ICD interventions was 34%, mostly for treatment of monomorphic VT in 52%, polymorphic VT in 13%, and VF in 35%. Seventy-one percent of VA were terminated by overdrive pacing, 29% by shock. Patients with a history of VA before LVAD implantation had a significantly higher 1-year rate for ICD therapy compared with LVAD patients with a primary prevention ICD indication LVAD patients (50 vs. 24%). Similarly, patients with non-ischaemic cardiomyopathy had a significantly higher risk for ICD therapy than patients with ischaemic heart disease (50 vs. 22%). CONCLUSION: Implantable cardioverter-defibrillator therapy is safe and effective in LVAD patients. Ventricular arrhythmias leading to ICD intervention occur frequently in 34% of LVAD patients after 1 year, with large variations depending on the underlying cardiac disease and previous arrhythmia history. Primary prevention ICD indication after LVAD implantation yields high rates of ICD intervention. A history of previous VA strongly predicts future use of ICD treatment after LVAD implantation.