t-wave oversensing occurs when the counter starts giving dual beeps for every cardiac cycle instead of one. this usually happens when the monitoring lead displays a tall t wave, which is also sharp. r wave sensing algorithms of the devices do not sense t wave because the slow rate of the t wave is much less than that of the r wave. but the slow rate of t waves may change with time and also beca...

background: differences in the quantity and distribution of coronary veins between patients with ischemic and non-ischemic cardiomyopathy might affect the potential for the left ventricular (lv) lead targeting in patients undergoing cardiac resynchronization therapy (crt). in the current study, we assessed and compared the suitability of the coronary venous system for the lv lead placement in i...

background: several competing geometric and hemodynamic factors are suggested as contributing mechanisms for functional mitral regurgitation (mr) in heart failure patients. we aimed to study the relationships between the severity of mr and the qrs duration and dyssynchrony markers in patients with ischemic or dilated cardiomyopathy. methods: w e prospectively evaluated 251 heart failure patient...

a 29-year-old woman was referred to our hospital due to exacerbation in dyspnea on exertion and easy fatigability. a known case of congenitally corrected transposition of the great vessels and congenital complete heart block, she had already received a permanent single-chamber pacemaker. decision was made to implant a biventricular pacemaker for the treatment of the failing heart. excellent cor...

background: the right ventricular (rv) dyssynchrony has not been studied extensively and the existing literature has established the effect of cardiac resynchronization therapy (crt) on the left ventricular (lv) dyssynchrony, but there is a dearth of data on the effect of crt on the forgotten ventricle . we sought to evaluate the presence of mechanical right ventricular dyssynchrony in patients...

BACKGROUND Studies of cardiac resynchronization therapy in addition to an implantable cardioverter defibrillator in patients with mild to moderate congestive heart failure had not been shown to reduce mortality until the recent RAFT trial (Resynchronization/Defibrillation for Ambulatory Heart Failure Trial). We performed a meta-analysis including the RAFT trial to determine the effect of cardia...

Cardiac resynchronization therapy improves clinical symptoms and prognosis of heart failure patients. However, it has been shown that up to 40% of patients do not respond to this therapy. Three main determinants of cardiac resynchronization therapy response have been identified: left ventricular dyssynchrony, left ventricular lead position, and extent and location of myocardial scar tissue. Two...

BACKGROUND Cardiac resynchronization therapy (CRT) is a medical device to help cardiac synchronized contractility by electrical impulses. Improvement of symptoms and left ventricular systolic function, reducing hospital admissions and mortality in patients with moderate to severe heart failure are the main benefits of administration of cardiac resynchronization therapy. CASE REPORT In this ar...

Cardiac resynchronization represents a novel therapeutic strategy for the treatment of congestive heart failure due to systolic dysfunction. Since its modest beginnings in the 1990s, cardiac resynchronization therapy has gained widespread acceptance as a useful adjunct to pharmacologic therapy for congestive heart failure. Randomized trials have consistently shown functional improvement in pati...

The weight of evidence supporting the routine use of cardiac resynchronization therapy, or atrial-synchronized biventricular pacing, as a treatment for patients with moderate-to-severe chronic systolic heart failure and ventricular dyssynchrony is now quite substantial. Results from mechanistic studies, observational evaluations, and randomized, controlled trials have consistently demonstrated ...