The association of muscle hypertophy in the outflow tract of a ventricle with obstruction to blood flow during systole is being recognized with increasing frequency. This functional stenosis has long been known to appear in the hypertrophied right ventricle following surgical relief of pulmonary valve stenosis (Kirklin et al., 1953; Brock, 1955). It was recognized in the left ventricle by Brock...

This analysis concerns Fallot's tetralogy, a form of cyanotic congenital heart disease about which there is little information relating to the population of north east England, and attempts to assess the influence of familial and other variables possibly concerned in its aetiology. This disease of the heart is named after Fallot who described it in 1888, though it had been recognized as a clini...

HYPERTROPHIC CARDIOMYOPATHY (HCM) is characterized by symmetric or asymmetric hyper-trophy of the left and/or right ventricle (table 1). * It is a primary disorder of heart muscle in which the site and extent of the hypertrophic process are important in determining the disease manifestations.' Ventricular (asymmetric) septal hypertrophy is the commonest form of HCM (table 1) and is characterize...

BACKGROUND We report the predictors of long-term outcomes of symptomatic hypertrophic cardiomyopathy patients undergoing surgical relief of left ventricular outflow tract obstruction. METHODS AND RESULTS We studied 699 consecutive patients who have hypertrophic cardiomyopathy with severe symptomatic left ventricular outflow tract obstruction (47±11 years, 63% male) intractable to maximal medi...

The occurrence of exercise-induced dynamic obstruction of the left ventricular outflow tract in patients without cardiomyopathy has recently been reported. However, it is not known if this phenomenon is a normal response to exercise in healthy adults. We studied 23 healthy adults using exercise Doppler echocardiography. We measured the left ventricular outflow velocity at rest and after maximum...

I DIOPATHIC hypertrophic subaortic stenosis, in contrast to valvular, supravalvular, or discrete subaortic stenosis, is characterized by obstruction to left ventricular ejection, which may vary from moment to moment. Since the obstruction results from the contraction of the hypertrophied muscle in the left ventricular outflow tract during systole, it was anticipated that influences that tend to...

OBJECTIVES The goal of this study was to determine the prevalence and evolution of acquired right ventricular outflow tract obstruction (RVOTO) in the recipient twin in twin-twin transfusion syndrome (TTTS). BACKGROUND Twin-twin transfusion syndrome complicates 4% to 26% of diamniotic monochorionic twin gestations and is associated with high fetal morbidity and mortality. Cardiac dysfunction ...

Fifteen patients (median age 8.5 years) with fixed right ventricular outflow tract obstruction were evaluated by two-dimensional echocardiographically directed continuous wave Doppler ultrasound within 24 hours of cardiac catheterization. Pulmonary artery blood velocity measurements were determined from a real time spectral display of pulmonary artery flow profile and converted to pressure drop...

Idiopathic hypertrophic subaortic stenosis (IHSS) is characterized by subaortic obstruction to left ventricular (LV) outflow. However, the obstruction is variable and many patients have no resting gradient and no clinical evidence of IHSS. Although a characteristic systolic movement of the anterior mitral valve leaflet can be demonstrated echocardiographically in many patients with IHSS, this m...