Glenda Winson

Treatment of Obstructive Hypertrophic Cardiomyopathy Symptoms and Gradient Resistant to First-Line Therapy With β-Blockade or Verapamil

Background—There is controversy about preferred methods to relieve obstruction in hypertrophic cardiomyopathy patients still symptomatic after &bgr;-blockade or verapamil. Methods and Results—Of 737 patients prospectively registered at our institution, 299 (41%) required further therapy for obstruction for limiting symptoms, rest gradient 61±45, provoked gradient 115±49 mm Hg, and followed up for 4.8 years. Disopyramide was added in 221 (74%) patients and pharmacological control of symptoms was achieved in 141 (64%) patients. Overall, 138 (46%) patients had surgical relief of obstruction (91% myectomy) and 6 (2%) alcohol septal ablation. At follow-up, resting gradients in the 299 patients had decreased from 61±44 to 10±25 mm Hg (P<0.0001); New York Heart Association class decreased from 2.7±0.7 to 1.8±0.5 (P<0.0001). Kaplan–Meier survival at 10 years in the 299 advanced-care patients was 88% and did not differ from nonobstructed patients (P=0.28). Only 1 patient had sudden death, a low annual rate of 0.06%/y. Kaplan–Meier survival at 10 years in the advanced-care patients did not differ from that expected in a matched cohort of the US population (P=0.90). Conclusions—Patients with obstruction and symptoms resistant to initial pharmacological therapy with &bgr;-blockade or verapamil may realize meaningful symptom relief and low mortality through stepped management, adding disopyramide in appropriately selected patients, and when needed, by surgical myectomy.

Resection-Plication-Release for Hypertrophic Cardiomyopathy: Clinical and Echocardiographic Follow-Up

BACKGROUND Abnormal positioning and size of the mitral valve contribute to the systolic anterior motion and mitral-septal contact that are important components of obstructive hypertrophic cardiomyopathy (HCM). The RPR repair (resection of the septum, plication of the anterior leaflet, and release of papillary muscle attachments) addresses all aspects of this complex pathology. This study reports outcomes regarding effectiveness of the RPR repair. METHODS Fifty consecutive unselected patients (average age, 55.8 years) undergoing RPR repair for obstructive HCM from 1997 to 2007 were studied. Each patient underwent preoperative and postoperative transthoracic echocardiograms to document gradient, ejection fraction, degree of mitral regurgitation, and systolic anterior motion. Intraoperative transesophageal echocardiogram was used to guide all surgical repairs. Clinical follow-up included patient interviews to determine New York Heart Association (NYHA) status. RESULTS Concomitant operations were performed in 25 patients (50%). Postoperative mortality was 0%. Average mean left ventricular outflow tract gradients decreased from 134 +/- 40 to 2.8 +/- 8.0. Mitral regurgitation improved from a mean of 2.5 to 0.1 (p < 0.001). Average length of stay was 6.9 +/- 2.7 days. NYHA class improved from 3.0 +/- 0.6 to 1.2 +/- 0.5. Follow-up was 100%, with a mean of 2.5 +/- 1.8 years. Average mitral regurgitation at follow-up was 0.9, with no residual systolic anterior motion. CONCLUSIONS The RPR repair is safe and effective for symptomatic obstructive HCM. Our data support repair of the mitral valve that results in good intermediate outcomes with respect to gradient, mitral regurgitation, and clinical status.

Standing and Exercise Doppler Echocardiography in Obstructive Hypertrophic Cardiomyopathy: The Range of Gradients with Upright Activity

BACKGROUND The ideal provocative maneuver in patients with hypertrophic cardiomyopathy (HCM) is a subject of ongoing investigation. Standing is a fundamental activity of daily life. This study examined acquisition of standing, Valsalva, and post-exercise left ventricular outflow tract gradients in HCM. METHODS Rest supine, standing, and post-Valsalva gradients were measured in 98 consecutive patients with HCM who were referred for outpatient echocardiography. In 53 (54%) of the 98 patients, symptom-limited treadmill exercise was also performed, with gradients measured immediately after in the supine position. RESULTS Fifty-six (57%) of the 98 patients had resting gradient<30 mm Hg and would thus be characterized as nonobstructive at rest. In the 98 patients, median gradients were 25 mm Hg at rest (range 0-205 mm Hg), increasing to 44 mm Hg after standing (range 0-309 mm Hg), an increase of 76%, and were again higher after Valsalva, 64 mm Hg (range 0-256 mm Hg) (P<.001). In the 53 patients who had gradient assessed after exercise, they were higher still, 100 mm Hg (range 0-256 mm Hg) (P<.001). In 29 patients (30%), standing provoked a higher gradient than Valsalva. CONCLUSION Although standing increased gradients by 76%, it is not as potent a provocative maneuver as Valsalva or treadmill exercise. Nevertheless, standing is recommended as a physiologic provocative maneuver. In some patients standing may guide therapy; in others, the standing and exercise gradient provide a correct appreciation of the range of physiologically experienced gradients during daily upright activity.

Post-Prandial Upright Exercise Echocardiography in Hypertrophic Cardiomyopathy

To the Editor: Approximately one-third of patients with hypertrophic cardiomyopathy (HCM) experience symptom exacerbation after a meal, and the post-prandial (PP) state has been associated with an increase in left ventricular outflow tract (LVOT) gradients ([1][1]). Also, LVOT gradients are higher

Antihypertensive therapy in hypertrophic cardiomyopathy.

Patients with coexisting hypertrophic cardiomyopathy (HC) and hypertension present diagnostic and therapeutic dilemmas. A retrospective cohort study of patients with HC with coexisting hypertension referred to a specialized HC program was conducted. HC and hypertension were confirmed by strict criteria. Echocardiographic data were reviewed for peak instantaneous left ventricular outflow tract gradients, at rest and with provocation. Symptom control, left ventricular outflow tract gradients, and hypertension control were compared between the first and last visits. One hundred fifteen patients (94 obstructed and 21 nonobstructed) met the eligibility criteria for the study and were included in the analysis, with the mean follow-up duration of 36 months. Because of the treatment strategy, there was a significant decrease in the number of patients treated with direct vasodilators and an increase in the use of β blockers and disopyramide. Twenty-one obstructed patients (22%) required septal reduction therapy. Overall, in obstructed patients, peak instantaneous left ventricular outflow tract gradient at rest decreased from 48 to 14 mm Hg (p <0.01), which was accompanied by significant improvement in functional class (2.4 vs 1.8, p <0.01). The prevalence of uncontrolled hypertension decreased from 56% at the initial visit to 37% at the last visit (p = 0.01). The cohort had a low rate of adverse cardiovascular outcomes such as death, acute coronary syndromes, and stroke. In conclusion, the present study demonstrates that stepwise, symptom-oriented therapy is feasible and effective in patients with coexisting HC and hypertension.