Xavier Waintraub

Temporary transvenous VDD pacing as a bridge to permanent pacemaker implantation in patients with sepsis and haemodynamically significant atrioventricular block

AIMS Permanent pacemaker (PM) implantation is temporarily contraindicated in patients (pts) with sepsis. In patients with symptomatic atrioventricular (AV) block and infection, prolonged VVI pacing is therefore usually ensured by a ventricular pacing lead (PL) connected to an external PM generator. In patients with normal sinus function and heart failure, the VVI mode can exacerbate haemodynamic dysfunction. A single AV PL can be attractive to achieve physiological pacing. This study was designed to assess the efficacy and safety of temporary VDD pacing as a bridge to permanent PM implantation in patients with complete AV block until control of infection. METHODS AND RESULTS This study included eight patients with complete AV block and sepsis with negative blood culture. Due to the presence of congestive heart failure, a single bipolar AV PL connected to an external VDD PM generator. At VDD implantation, P-wave amplitude was 1.9 ± 1.6 mV and R-wave was 11.3 ± 5.2 mV. The ventricular pacing threshold was 0.53 ± 0.1 V for a 0.5 ms pulse. Antibiotic therapy was instituted in all patients. A permanent VDD or DDD PM was implanted after 8 ± 2.5 days of temporary VDD pacing. At permanent PM implantation, the mean brain natriuretic peptide level had decreased and sepsis was controlled in all patients. No recurrence of sepsis was observed with a mean follow-up of 15.8 ± 5.3 months. CONCLUSION Temporary VDD pacing is a safe and effective method to achieve prolonged AV physiological pacing in patients with AV block until infection has been controlled.

Relationship between New York Heart Association class change and ventricular tachyarrhythmia occurrence in patients treated with cardiac resynchronization plus defibrillator

AIMS In patients with advanced heart failure (HF) and prolonged QRS interval, cardiac resynchronization therapy (CRT) reduces symptoms and risk of death. The added benefit of an implantable cardioverter defibrillator (ICD) remains questionable in some patients. METHODS AND RESULTS In 332 HF patients treated with CRT-D (CRT with ICD) [65 +/- 10 years, 86% men, 23% New York Heart Association (NYHA) class II, 65% class III, and 11% class IV, 70% primary prevention, 55% ischaemic cardiomyopathy, left ventricular ejection fraction 25 +/- 7.5%, and QRS width 167 +/- 32 ms], we evaluated the relationship between functional status change, death at 6-month follow-up (FU), and the occurrence of ventricular tachyarrhythmia/ventricular fibrillation (VT/VF). A total of 68 patients (20.5%) experienced 1266 spontaneous episodes of VT/VF during FU. There was no difference in baseline characteristics between patients with or without VT/VF, except for ICD indication (primary or secondary prevention). Improvement in NYHA class was significantly associated with a decreased occurrence of VT/VF (P = 0.004). Sixteen patients who died had significantly more often VT/VF than the survivors (50 vs. 19%, P = 0.007). CONCLUSION Within the initial 6-month post-CRT therapy, 20% of patients received an appropriate ICD therapy. Patients improving on NYHA class (responders to CRT) have less VT/VF episodes than non-responders. Discriminant criteria for CRT response are awaited to optimize the choice of the device (CRT alone, defibrillator alone, or CRT-D).

Fibrillation atriale : le plus fréquent des troubles du rythme

The incidence of atrial fibrillation increases rapidly with population age. Atrial fibrillation essentially presents a problem of long-term management. Strategies of rhythm or rate control should be considered on a case-by-case basis for each individual. Anticoagulation treatment is indicated in most cases. Radiofrequency ablation by pulmonary vein isolation is an unquestionably innovative treatment but is reserved for selected patients.

Catheter ablation of organized atrial arrhythmias in orthotopic heart transplantation

BACKGROUND Organized atrial arrhythmias (OAAs) are common after orthotopic heart transplantation (OHT). Some controversies remain about their clinical presentation, relationship with atrial anastomosis and electrophysiologic features. The objectives of this retrospective study were to determine the mechanisms of OAAs after OHT and describe the outcomes of radiofrequency catheter ablation (RFCA). METHODS Thirty consecutive transplanted patients (mean age 48 ± 17 years, 86.6% male) underwent 3-dimensional electroanatomic mapping and RFCA of their OAA from 2004 to 2012 at our center. RESULTS Twenty-two patients had biatrial anastomosis and 8 had bicaval anastomosis. Macro-reentry was the arrhythmia mechanism for 96% of patients. The electrophysiologic diagnoses were: cavotricuspid isthmus (CTI)-dependent atrial flutter (AFL) in 93% of patients (n = 28); perimitral AFL in 3% (n = 1); and focal atrial tachycardia (FAT) in 3% (n = 1). In 5 patients with biatrial anastomosis, a right FAT was inducible. Primary RFCA success was obtained in 93% of patients. Mean follow-up time was 39 ± 26.8 months. Electrical repermeation between recipient and donor atria, present in 20% of patients (n = 6), did not account for any of the OAAs observed. Survival without OAA relapse at 12, 24 and 60 months was 93%, 89% and 79%, respectively. CONCLUSIONS CTI-dependent AFL accounted for most instances of OAA after OHT, regardless of anastomosis type. Time from transplantation to OAA was shorter with bicaval than with biatrial anastomosis. RFCA was safe and provided good long-term results.

Implantable cardioverter-defibrillators in end-stage heart failure patients listed for heart transplantation: Results from a large retrospective registry.

BACKGROUND Implantable cardioverter-defibrillators (ICDs) are recommended in patients with low ejection fraction. However, the survival benefit of ICDs in patients with end-stage heart failure listed for heart transplantation is unclear. AIM To evaluate the ICD benefit on mortality in this population. METHODS Three hundred and eighty consecutive patients listed for heart transplantation between 2005 and 2009 in one tertiary heart transplant centre were enrolled in a retrospective registry; 122 patients received an ICD before or within 3 months after being listed for heart transplantation (ICD group). Predictors of death on the waiting list were assessed by Cox regression. RESULTS Overall, 15.6% of patients died while awaiting heart transplantation. Non-ICD patients presented more often haemodynamic compromise requiring mechanical circulatory support (29.1% vs. 9.8%; P<0.001), and were more likely to die while on the waiting list (19.0% vs. 8.3%; log-rank P=0.001). However, in the multivariable model, ICD did not remain an independent predictor of death. Need for mechanical circulatory support (P<0.001), low ejection fraction (P=0.001) and registration on the regular list (P=0.008) were the only independent predictors of death. Death was mainly caused by haemodynamic compromise (76.3% of deaths), which occurred more frequently in the non-ICD group (14.7% vs. 5.8%; log-rank P=0.002). Unknown/arrhythmic deaths did not differ significantly between the two groups (3.9% vs. 1.7%; log-rank P=0.21). ICD-related complications occurred in 21.4% of patients, mainly as a result of postoperative worsening of heart failure (11.9%). CONCLUSION Haemodynamic failure appears as the main determinant of mortality in patients with end-stage heart failure awaiting heart transplantation. ICD seems to have little benefit on survival in this population.

Pathophysiology of atrial fibrillation: insights into the renin-angiotensin system.

INTRODUCTION Atrial fibrillation is, to date, a major problem of public health with an important cost in the health care system. DISCUSSION The therapeutic strategies for atrial fibrillation are complex and their outcomes have been disappointing globally. New ablative techniques have brought important advances but the patients profile has to be taken into account in the choice of the therapeutic strategies. The renin-angiotensin system plays a major role in the phenomena of remodelling following the onset of atrial fibrillation. CONCLUSION Drugs blocking the renin-angiotensin system can have a real place in the treatment of atrial fibrillation, not only to maintain sinus rhythm but primarily to prevent cardiovascular accidents in these patients with atrial fibrillation and in some cases to prevent the occurrence of atrial fibrillation, for example in hypertensive patients.

Hypogonadism as a Reversible Cause of Torsades de Pointes in Men

Long QT intervals corrected for rate (QTc) >480 to 500 milliseconds predispose to the polymorphic ventricular tachycardia torsades de pointes (TdP).1 Because QTc is shorter and TdP is less frequent in men than in women and because testosterone shortens ventricular repolarization, we examined the effect of hypogonadism and androgen deprivation therapy (ADT) on QTc and TdP risk.2 We prospectively evaluated testosterone and related plasma levels in each man seen with TdP (n=7) over 19 months at a single university hospital (Hopital Pitie-Salpetriere, Paris, France, Commission nationale de l’informatique et des libertes No. 1491960v0, patients’ informed consent obtained). We then analyzed the European pharmacovigilance database (up to June 2017, URL: https://clinicaltrials.gov, Unique identifier: NCT03193138) searching for QTc/TdP adverse drug reactions ( Medical Dictionary for Regulatory Activities terms: long-QT syndrome [LQT], ECG QT-prolonged, and TdP) associated with ADT, and we performed a cross-sectional analysis of the association between the International Classification of Diseases revisions 9 and 10 codes for LQT/TdP and hypogonadism in 1.1 million men in a US electronic health record cohort (up to November 2017, Vanderbilt University Medical Center, Institutional Review Board approval no. 171796).3 Hypogonadism was diagnosed in 7 of 7 cases of TdP (Table). After correction of low testosterone …

Crossroads or “Flyovers” novel insights into ventricular tachycardia mechanisms: The path is twisting: MAURY et al.

Diverging channels of activation may be observed in some ventricular tachycardia (VT) using ultra‐high‐density mapping. We present here cases of such diverging activation patterns as observed from 60 consecutive VT activation maps using the Rhythmia system™ (Boston Scientific, Marlborough, MA, USA). Diverging directions of activation in the same area with “crossroads” or “flyover” pattern can be traced, implying recording of independent multilayer channels. Adaptation of current automated recording by the 3D mapping system is mandatory for better investigating this phenomenon.

Reversible mechanical atrioventricular block during cryoablation for paroxysmal atrial fibrillation with a 28 mm balloon

Cryoablation of paroxysmal atrial fibrillation is an increasingly common procedure for treatment of symptomatic patients after failure of or intolerance to antiarrhythmic drug therapy. Atrioventricular (AV) block during cryoablation therapy is an uncommon complication. We present a case of a transient mechanical AV block occurring during manipulation of a 28 mm cryoballoon catheter before cryoenergy delivery around the right inferior pulmonary vein (RIPV). The main hypothesis is a mechanical bump of the AV node.