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The aim of this study was to explore the association between mechanical dyssynchrony of the left ventricle before cardiac resynchronization therapy (CRT) and improvement of mitral regurgitation (MR) after CRT. MR is very frequent among patients with dilated cardiomyopathy and conduction delay. Echocardiograms (pre-CRT and 12 ± 3.8 months thereafter) of 314 patients with dilated cardiomyopathy and any degree of MR, who underwent CRT device implantation according to guidelines, were analyzed. Left ventricular (LV) mechanical dyssynchrony was assessed by apical rocking (ApRock) and septal flash (SF), while MR severity was graded from I to IV on the basis of vena contracta width, regurgitation jet size, and proximal isovelocity surface area. At baseline, 30% of patients presented with severe MR (grade III or IV). In 62% of patients, MR decreased after CRT, and these patients more frequently had left bundle branch block, had more severe MR, had more dilated left ventricles, had lower ejection fractions, and more often had ApRock and SF. Reverse remodeling was more frequent among patients with MR reduction (ΔLV end-systolic volume −35.5% ± 27.2% vs −4.1% ± 33.2%; P < 0.001). In a multivariable logistic stepwise regression, only ApRock (odds ratio [OR]: 3.8; 95% CI: 1.7-8.5; P = 0.001), SF (OR: 3.6; 95% CI: 1.6-7.9; P = 0.002), and baseline MR (OR: 1.4; 95% CI: 1.0-1.9; P = 0.046) remained significantly associated with MR reduction. ApRock, SF, and severity of MR at baseline are strongly associated with MR reduction after CRT, while LV reverse remodeling is its underlying mechanism. Therefore, in patients with heart failure with LV dyssynchrony on optimal medical treatment, CRT should be the primary treatment attempt for relevant MR. [Display omitted] [ABSTRACT FROM AUTHOR]

Objectives The aim of this study was to compare the volumetric response and the long-term survival after cardiac resynchronization therapy (CRT) in patients with intrinsic left bundle branch block (LBBB) versus chronic right ventricular pacing (RVP) with respect to the presence of mechanical dyssynchrony (MD). Background Chronic RVP induces an iatrogenic LBBB and asynchronous left ventricular contraction that is potentially reversible by upgrading to CRT. Methods A total of 914 patients eligible for CRT (117 with conventional pacemakers and 797 with intrinsic LBBB) were included in the study. MD was visually assessed before CRT and was defined as the presence of either apical rocking and/or septal flash on baseline echocardiograms. Patients with a left ventricular end-systolic volume decrease of ≥15% during the follow-up were considered responders. Patients were followed for all-cause mortality during the median follow-up of 48 months (interquartile range: 29 to 66 months). Results MD was observed in 51% of patients with RVP versus 77% in patients with intrinsic LBBB (p < 0.001). Patients with RVP and MD had a similar likelihood of volumetric response as did patients with intrinsic LBBB and MD (adjusted odds ratio: 0.71; 95% confidence interval: 0.33 to 1.53; p = 0.385). There was no significant difference in long-term survival between patients with RVP and intrinsic LBBB (adjusted hazard ratio: 1.101; 95% confidence interval: 0.658 to 1.842; p = 0.714). Patients with visual MD and either intrinsic LBBB or RVP had a more favorable survival than those without MD (p < 0.001). Conclusions The likelihood of volumetric response and a favorable long-term survival of patients with RVP was similar to those of patients with intrinsic LBBB and were mainly determined by the presence of MD and not by the nature of LBBB. [ABSTRACT FROM AUTHOR]

Objectives This study sought to investigate the influence of scar extent and location on the motion pattern of the left ventricle (LV) and its interaction with LV conduction delays. Background Different echocardiographic parameters have been proposed to identify responders to cardiac resynchronization therapy based on the detection of LV mechanical dyssynchrony. However, the impact of infarct scar on the diagnostic performance of these parameters remains unknown. Methods We included 11 healthy volunteers and 122 patients with normal and severely reduced function, wide and narrow QRS, as well as with and without infarct scar. Location and extent of infarct scar was defined by contrast-enhanced cardiac magnetic resonance. Influence of infarct scar on the motion pattern of the LV was examined by measuring direction and amplitude of apical rocking. The influence of scar on different echocardiographic dyssynchrony parameters was investigated. Results Scar in the absence of conduction delay caused most apical rocking in the presence of 3 to 4 infarct segments. Pure apical infarction caused no rocking. In wide QRS patients without infarct scar, apical rocking was mainly dominated by the conduction delay, whereas in wide QRS patients with ischemic cardiomyopathy, this pattern was modulated by the scar. Apical rocking was inversely related to scar extent (r = −0.54, p < 0.05). Apical rocking was better associated with cardiac resynchronization therapy response than conventional dyssynchrony measurements. Conclusions LV motion patterns are mainly dominated by conduction delays, but they are also modulated by infarct scar. Higher scar burden resulted in less pronounced apical rocking. Apical rocking is more strongly associated with cardiac resynchronization therapy response than with conventional echocardiographic parameters and may therefore be used as a screening parameter. [ABSTRACT FROM AUTHOR]

Abstract: Background: It has been suggested that patients with chronic HF and atrial fibrillation (AF) may respond differently to beta-blockers than those in sinus rhythm (SR). Methods: In this predefined analysis of the CIBIS-ELD trial, a total of 876 chronic HF patients (164 patients with AF) were randomized to bisoprolol or carvedilol. During the 12-week-treatment phase, beta-blockers were doubled fortnightly up to the target dose or maximally tolerated dose, which was maintained for 4weeks. Results: Patients with AF had lower left ventricular ejection fraction (LVEF), exercise capacity, self-rated health, quality of life (QoL) scores for both SF36 physical and psychosocial component, and higher NYHA class than those in SR. Beta-blocker titration was associated with clinical improvement in both AF and SR patients: LVEF, 6-minute walk distance, physical and psychosocial components of QoL scores, self-rated health and NYHA class (p<0.05, for all). The extent of improvement did not differ between patients with AF and in SR and did not differ between bisoprolol and carvedilol. Heart rate (HR) at baseline was higher in the AF group, and remained higher until the end of the trial. Patients with higher baseline HR had larger reductions in HR, regardless of rhythm. AF patients more frequently reached target beta-blocker dose compared to those in SR (p<0.005). Conclusions: Elderly patients with chronic HF and AF derive comparable clinical benefits from beta-blocker titration as those in SR. Patients with AF tolerate higher beta-blocker doses than those in SR, which appears to be related to higher baseline HR. [Copyright &y& Elsevier]

Abstract: In a few patients with acute proximal thrombotic occlusion of the left anterior descending coronary artery (LAD), tall ischemic T waves never evolve into ST-segment elevation. This was recently inaccurately reported as a “novel sign” of proximal LAD occlusion. It has been speculated that the absence of ST-segment elevation could be attributed to the large area of transmural ischemia, the anatomic variant of Purkinje fibers, or to lack of activation of sarcolemal adenosine triphosphate–potassium channels. This electrocardiographic picture was recently explained by changes in the subendocardial but not in the epicardial action potential, suggesting subendocardial ischemia as the underlying mechanism. We present a patient with thrombotic lesion of proximal LAD, static precordial ST-segment depression, and tall T waves who underwent primary percutaneous intervention and stent placement. Surprisingly, total thrombotic stent occlusion on the following day was associated with ST-segment elevation in precordial leads, indeed supporting the concept of the regional subendocardial ischemia that was first described more than a decade ago. [Copyright &y& Elsevier]

Background: Simvastatin, a 3-hydroxy-3-methylglutarylcoenzyme A reductase inhibitor, is indicated for the treatment of hypercholesterolemia and plays an important role in both the primary and secondary prevention of cardiovascular disease. Danazol is a steroid analogue approved for the treatment of endometriosis, fibrocystic breast disease, and hereditary angioedema. Despite not being licensed, danazol has been used for other off-label indications, such as idiopathic thrombocytopenic purpura (ITP), paroxysmal nocturnal hemoglobinuria, and aplastic anemia. Objective: We report a case of fatal rhabdomyolysis that occurred after concomitant administration of simvastatin and danazol in a patient with ITP. Case summary: An 80-year-old white male (height, 182 cm; weight, 90 kg) presented to the emergency department of the Clinical Hospital Centre Zemun, Belgrade, Serbia, with head injuries after an accidental fall caused by generalized weakness. He denied other complaints, except fatigue, mild pretibial edema, and progressive bilateral leg pain and cramping that began 7 days before. At the time of presentation, he was receiving aspirin 100 mg/d, clopidogrel 75 mg/d, ramipril 2.5 mg/d, pantoprazole 40 mg/d, danazol 600 mg/d, prednisone 60 mg/d, simvastatin 40 mg/d, and longacting insulin 24 IU/d. After the injuries were treated, he was diagnosed with collapse and nasal contusion, and discharged without any changes in his therapy. Two days after initial presentation, the patient was readmitted to the hospital due to nausea, dark urine, and oliguria. All clinical signs (oliguria, dark urine, muscle pain, and tenderness) and laboratory markers (creatine kinase levels ∼100 times the upper limit of normal, along with hyperkalemia, hyperphosphatemia, and hypoalbuminemia) were consistent with severe rhabdomyolysis. Despite intravenous hydration, forced diuresis, and hemodialysis, oliguria persisted and the patient died 6 days after admission. A score of 5 on the Naranjo adverse drug reaction probability scale was consistent with a probable association of rhabdomyolysis and concomitant treatment with simvastatin and danazol in this patient. Conclusions: Statin-induced rhabdomyolysis must be considered whenever muscle or motor symptoms occur, especially when concomitant treatment with known inhibitors of statin metabolism is administered. Patients must be strictly monitored and the statin should be promptly discontinued with the onset of first signs and symptoms of myopathy. Clinicians should be aware of the potentially fatal consequences of both approved and unapproved treatments and be alert for the early detection of toxicity. [Copyright &y& Elsevier]

Abstract: Background: Wellens syndrome refers to a distinct electrocardiographic pattern of deeply inverted or biphasic T waves in the anterior precordial leads, in the presence of critical proximal stenosis of the left anterior descending coronary artery (LAD). The natural history of the syndrome is an extensive myocardial infarction within weeks of hospital admission. Case Report: This report describes a 63-year-old man in whom typical electrocardiographic signs of Wellens syndrome advanced to persistent ST-segment elevation within 7min of presentation. Extensive anterior myocardial infarction (AMI) was aborted by primary percutaneous coronary intervention of a sub-occluded proximal LAD. Conclusion: Given the large area of the left ventricle supplied by a sub-occluded LAD, devastating AMI could have been expected and may have resulted in serious ventricular dysfunction and death. Therefore, early recognition of Wellens syndrome is essential and can be lifesaving. [Copyright &y& Elsevier]