Cardiac resynchronization therapy in patients with heart failure and moderately reduced ejection fraction: Could it trigger a super-response?

Background/Aim Despite the well-established benefits of cardiac resynchronization therapy (CRT) in heart failure (HF) patients with left ventricular ejection fraction (LVEF) ≤35%, many patients with less reduced EF remain refractory to optimized medical treatment and at high risk of morbidity and mortality. The objective of the study is to evaluate the effects of CRT in optimally treated patients with New York Heart Association (NYHA) classes II–IV, LVEF of 36–45%, and left bundle branch (LBBB), including clinical, structural and biochemical response. Methods A selected group of HF patients have been implanted with CRT-P devices and were followed up for 6 months at 4, 12 and 24 weeks. Clinical assessment included NYHA class, quality of life and 6-min walk distance (6 MWD) test. Echocardiographic assessment included LV dimensions and function and left atrial volume. Serum N-terminal pro b-type natriuretic peptide (NT-ProBNP) was measured at the same intervals. Results This prospective single center study included 23 patients. NYHA functional class significantly improved after CRT-P (p < 0.0001), associated with improvement in QOL (p < 0.0001) and 6 MWD, which increased, from 145.7 ± 20.1 m to 219.5 ± 42.2 m (p < 0.0001). Mean QRS duration showed significant shortening from 164.4 ± 13.2 ms to 126.4 ± 13.6 ms (p < 0.0001). CRT induced reverse remodeling with reduction in both left ventricular end diastolic diameter (LVEDD) from 68.95 ± 5.05 mm to 62.8 ± 4.47 mm, p = 0.0002 and left ventricular end systolic diameter (LVESD) from 54.1 ± 4.5 mm to 46.5 ± 4.1 mm, p < 0.0001, and significant increase in LVEF (from 40.3 ± 2.8 to 48.3 ± 4.2 mm, p < 0.0001). The biochemical response to CRT showed significant reduction in serum NT-ProBNP from 1025.6 ± 363.1 pg/ml to 594.9 ± 263.5 pg/ml (p < 0.0001). Conclusions Symptomatic HF patients on maximal optimized medical treatment who have LBBB and baseline LVEF 35–45% appeared to derive significant clinical and structural benefit from CRT.

Compromising bradycardia: management in the Emergency Department of National Heart Institute

The need to treat bradycardias is dictated primarily by the clinical Presentation of the patient [1]. Bradycardia may bean incidental finding in asymptornatic patients [2]. On the other hand, bradycardia may present with haemodynamic instability and loss of consciousness [3]. Out of the bradycardic rhythms to be encountered in these patients, high grade atrioventricular-block represents a significant portion [4]. Compromising bradycardia requires an effective diagnostic and therapeutic approach [1]. The goal of initial management is stabilization by increase of the ventricular rate by both pharmacological and non-pharmacological interventions, sometimes even cardiopulmonary resuscitation is required [5]. A careful clinical workup for potential causes, including ischacmic and non-ischaemic aetiologies, is crucial for successful management [6]. There are only a few reports available on the management and outcome of patients presenting with compromising bradycardia to the emergency department [ED] [1]. This study include 210 consecutive patients, with compromising bradycardia, admitted to the emergency department of National Heart Institute [tertiary Care hospital] within eight month period, 107 patients [51%] females, 103 patients [49%] males, whose age ranged from 25 to 89 years. The aim of this study is to report the incidence, symptoms, presenting rhythm, underlying mechanism, management, and outcome of patients presenting with compromising bradycardia to the emergency department and to assess the incidence of patients in need for temporary and permanent pacing. All patients were subjected to full history taking, general and local cardiac examination, resting 12-leads ECG and routine laboratory investigation

Clinical predictors and outcomes associated with acute return of pulmonary vein conduction during pulmonary vein isolation for treatment of atrial fibrillation

Radiofrequency ablation has become a common trend in management of cases of AF refractory to medical treatment. Recurrence of AF is a common observation both acutely and late during follow up. To determine the clinical predictors of acute reconnection of pulmonary vein potentials during PVI and late recurrence of AF on follow-up, respectively. A cohort of 14 patients referred to the EP labs of the NHI and Ain Shams University for PVI between January 2007 and February 2008 were studied. PVI of arrhythmogenic PVs was performed segmentally. PVI was defined as entry and exit block using a multipolar Lasso catheter. All veins were resampled to confirm isolation after 20-60niinutes. There were 14 patients who underwent isolation of 56 pulmonary veins during the study period. Acute reconnection of at least one vein occurred in 7 patients [50%] and 10 of the 56 pulmonary veins targeted [18%]. The left superior PV was most likely to acutely recover conduction compared with the other veins. Predictors of acute reconnection could not be accounted for given possible technical difficulties and the small sample size. During the three month follow up period, recurrence of AF occurred in 3 patients representing 21.4% of the cohort. It was found to be higher in female gender, left atrial size>or equal 4.Scms, age older than 50 years, non-paroxysmal type of AF and an EF of less than 50%. Many clinical criteria can affect acute reconnection of PVPs during PVI for patients with AF. According to previous studies large left atrium, older age, hypertension, non-paroxysmal type of AF are the most likely acute predictors. As regards short term follow-up, factors that could be considered include gender, age, left atrial size, EF and type of AF. The importance of detection of acute recurrence of PVPs and re-isolation has also become evident through this study