Prevalence of systolic anterior motion of the mural (posterior) leaflet of the mitral valve in hypertrophic cardiomyopathy: an echocardiographic study

Persistent ST segment elevation: a new ECG finding in hypertrophic cardiomyopathy

Hypertrophic cardiomyopathy is a primary disease of myocardium resulting in myocardial hypertrophy without any inciting pressure or volume overload. The typical triad of symptoms includes exertional angina, syncope, and shortness of breath. Sudden cardiac death, the most dreadful complication of this disorder, can be the first manifestation of the disease and is more common in young patients. Elderly patients, on the other hand, may have a relatively benign course with normal or near-normal life span. The electrocardiogram (ECG) and echocardiography are the two most useful measures to diagnose hypertrophic cardiomyopathy. The electrocardiographic features of hypertrophic cardiomyopathy are numerous, including ST segment elevation that may simulate other ST segment elevation syndromes, including acute myocardial infarction, variant angina pectoria, acute pericarditis, bundle branch blocks, ventricular paced rhythm, dyskinetic ventricular segment, ventricular aneurysm, left ventricular hypertrophy, Wolff-Parkinson-White syndrome, and early repolarization syndrome. This report describes a case of an asymptomatic patient who presented with ST segment elevation of acute injury type and, therefore, was admitted to rule out silent myocardial infarction. Myocardial infarction was ruled out by cardiac enzyme levels, but ST segment elevation remained persistent in all of the subsequent ECGs. Echocardiography was performed, which clearly showed hypertrophic cardiomyopathy with left ventricular outflow tract obstruction and a high intracavity pressure gradient. Subsequently, retrieval of old ECGs showed a similar type of ST segment elevation in the patient's previous ECGs.

Transesophageal Doppler echocardiography in obstructive hypertrophic cardiomyopathy: clarification of pathophysiology and importance in intraoperative decision making

To better understand the pathophysiology of obstruction of left ventricular outflow in hypertrophic cardiomyopathy and to determine the value of intraoperative transesophageal Doppler echocardiography in decision making, 32 consecutive patients undergoing ventriculomyectomy were assessed. The mean preoperative left ventricular outflow gradient was 83 +/- 39 mm Hg and the mean basal septal width was 24 +/- 6 mm. Compared with transesophageal findings in 10 normal control subjects, the mitral leaflets were longer and the coaptation point was abnormal in the patients with obstructive hypertrophic cardiomyopathy (anterior and posterior leaflet lengths in the patients were 31 +/- 4 vs. 22 +/- 3 mm in the control group [p less than 0.00001] and 20 +/- 2 vs. 15 +/- 3 mm in the control group [p less than 0.00001]). The coaptation point in the patient group was in the body of the leaflets at a mean of 9 +/- 2 mm from the anterior leaflet tip, whereas it was at or within 3 mm of the leaflet tip in the normal group. During early systole, the distal third to half of the anterior mitral leaflet angled sharply anteriorly and superiorly (systolic anterior motion), resulting in leaflet-septal contact and incomplete mitral leaflet coaptation in mid-systole. This caused the formation of a funnel, composed of the distal parts of both leaflets, that allowed a jet of posteriorly directed mitral regurgitation to occur in mid- and late systole. The sequence of events in systole was eject/obstruct/leak. Transesophageal echocardiography was also helpful in planning the extent of the resection, assessing the immediate result and excluding important complications. In successful cases, the post-myectomy study showed 1) a dramatic thinning of the septum, with widening of the left ventricular outflow tract to a width similar to that in the normal subjects, 2) resolution of systolic anterior motion and the left ventricular outflow tract color mosaic, and marked reduction or abolition of mitral regurgitation despite persistence of abnormal mitral leaflet length and an abnormal mitral leaflet coaptation point. The routine use of transesophageal echocardiography in patients undergoing surgical myectomy for the treatment of obstructive hypertrophic cardiomyopathy is recommended.