Hypertrophic cardiomyopathy with dynamic obstruction and high left ventricular outflow gradients associated with paradoxical apical ballooning.

BACKGROUND: Acute left ventricular (LV) apical ballooning with normal coronary angiography occurs rarely in obstructive hypertrophic cardiomyopathy (OHCM); it may be associated with severe hemodynamic instability. METHODS, RESULTS: We searched for acute LV ballooning with apical hypokinesia/akinesia in databases of two HCM treatment programs. Diagnosis of OHCM was made by conventional criteria of LV hypertrophy in the absence of a clinical cause for hypertrophy and mitral-septal contact. Among 1519 patients, we observed acute LV ballooning in 13 (0.9%), associated with dynamic left ventricular outflow tract (LVOT) obstruction and high gradients, 92 ± 37 mm Hg, 10 female (77%), age 64 ± 7 years, LVEF 31.6 ± 10%. Septal hypertrophy was mild compared to that of the rest of our HCM cohort, 15 vs 20 mm (P < 0.00001). An elongated anterior mitral leaflet or anteriorly displaced papillary muscles occurred in 77%. Course was complicated by cardiogenic shock and heart failure in 5, and refractory heart failure in 1. High-dose beta-blockade was the mainstay of therapy. Three patients required urgent surgical relief of LVOT obstruction, 2 for refractory cardiogenic shock, and one for refractory heart failure. In the three patients, surgery immediately normalized refractory severe LV dysfunction, and immediately reversed cardiogenic shock and heart failure. All have normal LV systolic function at 45-month follow-up, and all have survived. CONCLUSIONS: Acute LV apical ballooning, associated with high dynamic LVOT gradients, may punctuate the course of obstructive HCM. The syndrome is important to recognize on echocardiography because it may be associated with profound reversible LV decompensation.

Mitral Leaflet Shortening as an Ancillary Procedure in Obstructive Hypertrophic Cardiomyopathy.

BACKGROUND: Mitral leaflet elongation is common in hypertrophic cardiomyopathy (HCM), contributes to obstructive physiology, and presents a challenge to the dual surgical goals of abolition of outflow gradients and abolition of mitral regurgitation. Anterior leaflet shortening, performed as an ancillary surgical procedure during myectomy, is controversial. METHODS: This was a retrospective study of all patients undergoing myectomy from January 2010 to March 2020, with analysis of survival and echocardiographic results. The study compared outcomes of patients treated with myectomy and concomitant mitral leaflet shortening with patients treated with myectomy alone. Over this time, the technique for mitral shortening evolved from anterior leaflet plication to residual leaflet excision (ReLex). RESULTS: Myectomy was performed in 416 patients aged 57.5 ± 13.6 years, and 204 (49%) patients were female. Average follow-up was 5.4 ± 2.8 years. Survival follow-up was complete in 415 patients. Myectomy without valve replacement was performed in 332 patients, of whom 192 had mitral valve shortening (58%). Mitral leaflet plication was performed in 73 patients, ReLex in 151, and both procedures in 32. Hospital mortality for patients undergoing myectomy was 0.7%. At 8 years, cumulative survival was 95% for both the myectomy combined with leaflet shortening group and the myectomy alone group, with no difference in survival between the 2 groups. There was no difference in survival between the anterior leaflet plication and ReLex groups. Echocardiography 2.5 years after surgery showed a decrease in resting and provoked gradients, mitral regurgitation, and left atrial volume and no difference in key variables between patients who underwent ancillary leaflet shortening and patients who underwent myectomy alone. CONCLUSIONS: These results affirm that mitral shortening may be an appropriate surgical judgment for selected patients.

Clinical Course and Treatment of Patients With Apical Aneurysms Due to Hypertrophic Cardiomyopathy.

Background: There is controversy about risk of malignant arrhythmias and stroke in patients with apical aneurysms in hypertrophic cardiomyopathy (HCM). Objectives: The aim of this study was to estimate the associations of aneurysm size and major HCM risk factors with the incidence of lethal and potentially lethal arrhythmias and to estimate incidence of unexplained stroke. Methods: In 108 patients (age 57.4 ± 13.5 years, 37% female) from 3 HCM centers, we assessed American Heart Association/American College of Cardiology guidelines risk factors and initial aneurysm size by echocardiography and cardiac magnetic resonance imaging and assessed outcomes after median 5.9 (IQR: 3.7-10.0) years. Results: Implantable cardioverter defibrillator discharges or sudden cardiac death (SCD) occurred in 21 (19.4%) patients. Of patients with a risk factor, 55% subsequently had ventricular tachycardia (VT), ventricular fibrillation (VF), or SCD at follow-up, compared with 10% in those who did not (P < 0.001). The upper tercile of size had a 5-year cumulative risk of 35%, while the lower tercile had 5-year risk of 6% (P = 0.0046). In those with the smallest aneurysms <2 cm2 and also without risk factors VT, VF, or SCD occurred in only 2.5%. Clinical atrial fibrillation (AF) was prevalent, occurring in 49 (45%). Stroke was commonly associated with AF. Stroke without conventional cause had an incidence of 0.5%/year. Surgery in 19% was effective in reducing symptoms. VT ablation and surgery were moderately effective in preventing recurrent VT. Conclusions: Risk factors and aneurysm size were associated with subsequent VT, VF, or SCD. Patients with aneurysms in the lowest tercile of size have a low cumulative 5-year risk. Clinical AF occurred frequently. Stroke prevalence in absence of known stroke etiologies is uncommon and comparable to risk of severe bleeding.

Apical Aneurysms and Mid-Left Ventricular Obstruction in Hypertrophic Cardiomyopathy.

BACKGROUND: Apical left ventricular (LV) aneurysms in hypertrophic cardiomyopathy (HCM) are associated with adverse outcomes. The reported frequency of mid-LV obstruction has varied from 36% to 90%. OBJECTIVES: The authors sought to ascertain the frequency of mid-LV obstruction in HCM apical aneurysms. METHODS: The authors analyzed echocardiographic and cardiac magnetic resonance examinations of patients with aneurysms from 3 dedicated programs and compared them with 63 normal controls and 47 controls with apical-mid HCM who did not have aneurysms (22 with increased LV systolic velocities). RESULTS: There were 108 patients with a mean age of 57.4 ± 13.5 years; 40 (37%) were women. A total of 103 aneurysm patients (95%) had mid-LV obstruction with mid-LV complete systolic emptying. Of the patients with obstruction, 84% had a midsystolic Doppler signal void, a marker of complete flow cessation, but only 19% had Doppler systolic gradients ≥30 mm Hg. Five patients (5%) had relative hypokinesia in mid-LV without obstruction. Aneurysm size is not bimodal but appears distributed by power law, with large aneurysms decidedly less common. Comparing mid-LV obstruction aneurysm patients with all control groups, the short-axis (SAX) systolic areas were smaller (P < 0.007), the percent SAX area change was greater (P < 0.005), the papillary muscle (PM) areas were larger (P < 0.003), and the diastolic PM areas/SAX diastolic areas were greater (P < 0.005). Patients with aneurysms had 22% greater SAX PM areas compared with those with elevated LV velocities but no aneurysms (median: 3.00 cm2 [IQR: 2.38-3.70 cm2] vs 2.45 [IQR: 1.81-2.95 cm2]; P = 0.004). Complete emptying occurs circumferentially around central PMs that contribute to obstruction. Late gadolinium enhancement was always brightest and the most transmural apical of, or at the level of, complete emptying. CONCLUSIONS: The great majority (95%) of patients in the continuum of apical aneurysms have associated mid-LV obstruction. Further research to investigate obstruction as a contributing cause to apical aneurysms is warranted.

Using Deep-Learning Algorithms to Simultaneously Identify Right and Left Ventricular Dysfunction From the Electrocardiogram.

OBJECTIVES: This study sought to develop DL models capable of comprehensively quantifying left and right ventricular dysfunction from ECG data in a large, diverse population. BACKGROUND: Rapid evaluation of left and right ventricular function using deep learning (DL) on electrocardiograms (ECGs) can assist diagnostic workflow. However, DL tools to estimate right ventricular (RV) function do not exist, whereas those to estimate left ventricular (LV) function are restricted to quantification of very low LV function only. METHODS: A multicenter study was conducted with data from 5 New York City hospitals: 4 for internal testing and 1 serving as external validation. We created novel DL models to classify left ventricular ejection fraction (LVEF) into categories derived from the latest universal definition of heart failure, estimate LVEF through regression, and predict a composite outcome of either RV systolic dysfunction or RV dilation. RESULTS: We obtained echocardiogram LVEF estimates for 147,636 patients paired to 715,890 ECGs. We used natural language processing (NLP) to extract RV size and systolic function information from 404,502 echocardiogram reports paired to 761,510 ECGs for 148,227 patients. For LVEF classification in internal testing, area under curve (AUC) at detection of LVEF ≤40%, 40% < LVEF ≤50%, and LVEF >50% was 0.94 (95% CI: 0.94-0.94), 0.82 (95% CI: 0.81-0.83), and 0.89 (95% CI: 0.89-0.89), respectively. For external validation, these results were 0.94 (95% CI: 0.94-0.95), 0.73 (95% CI: 0.72-0.74), and 0.87 (95% CI: 0.87-0.88). For regression, the mean absolute error was 5.84% (95% CI: 5.82%-5.85%) for internal testing and 6.14% (95% CI: 6.13%-6.16%) in external validation. For prediction of the composite RV outcome, AUC was 0.84 (95% CI: 0.84-0.84) in both internal testing and external validation. CONCLUSIONS: DL on ECG data can be used to create inexpensive screening, diagnostic, and predictive tools for both LV and RV dysfunction. Such tools may bridge the applicability of ECGs and echocardiography and enable prioritization of patients for further interventions for either sided failure progressing to biventricular disease.

Endomyocardial Fibrosis Found Incidentally on Cardiac Imaging.

Endomyocardial fibrosis (EMF) is a rare disease in the developed world characterized by the fibrosis of the endocardium in one or both of the ventricles causing restrictive-type cardiomyopathy. We present a case of a 47-year-old Chinese female with a past medical history of breast cancer treated in 2014 currently on tamoxifen therapy presented to the cardiology office for multiple presyncopal and syncopal events at rest. She was found to have apical hypertrophic cardiomyopathy (HCM) on echocardiogram. Subsequently, cardiac magnetic resonance imaging (cMRI) showed severe apical hypertrophy without left ventricular aneurysm, and evidence of small apical thrombus with subendocardial enhancement. There was no resolution of the left ventricular thrombus after a year-long course of therapeutic anticoagulation, a finding more consistent with EMF. Though the diagnosis of EMF initially depends on echocardiographic findings, cMRI is an essential imaging modality that allows clinicians to easily differentiate between potential diagnoses with the information that it provides. Early diagnosis, differentiation, and treatment for HCM are important for a good prognosis.

Biventricular takotsubo syndrome with COVID-19 in an Asian male.

Coronavirus disease 2019 (COVID-19) has been shown to affect the cardiovascular system, and several cases of takotsubo syndrome (TTS) induced by COVID-19 have been reported. TTS predominantly affects postmenopausal women in western countries, but the prevalence in men is higher in Asian populations. It should be noted that male patients with either TTS or COVID-19 are associated with higher mortality. Despite the higher prevalence of TTS in Asian men, little is known about Asian men with TTS induced by COVID-19. This is a case report of a 60-year-old Asian male with biventricular TTS precipitated by COVID-19. He presented with acute respiratory distress syndrome, cardiogenic shock, and acute kidney injury. He required intubation, multiple vasopressors, and renal replacement therapy. The left ventricular ejection fraction was 15%, but it normalized in 5 weeks. The patient had a prolonged hospital stay in a critical condition, but was eventually discharged alive. The scarce literature about this condition in Asian male populations and the increasing number of COVID-19 cases in Asian countries highlight the rarity and importance of this case. Further studies are warranted to investigate the uneven sex distribution and outcomes of TTS triggered by COVID-19 in an Asian population. .

Syndrome of Reversible Cardiogenic Shock and Left Ventricular Ballooning in Obstructive Hypertrophic Cardiomyopathy.

Background Cardiogenic shock from most causes has unfavorable prognosis. Hypertrophic cardiomyopathy (HCM) can uncommonly present with apical ballooning and shock in association with sudden development of severe and unrelenting left ventricular (LV) outflow obstruction. Typical HCM phenotypic features of mild septal thickening, outflow gradients, and distinctive mitral abnormalities differentiate these patients from others with Takotsubo syndrome, who have normal mitral valves and no outflow obstruction. Methods and Results We analyzed 8 patients from our 4 HCM centers with obstructive HCM and abrupt presentation of cardiogenic shock with LV ballooning, and 6 cases reported in literature. Of 14 patients, 10 (71%) were women, aged 66±9 years, presenting with acute symptoms: LV ballooning; depressed ejection fraction (25±5%); refractory systemic hypotension; marked LV outflow tract obstruction (peak gradient, 94±28 mm Hg); and elevated troponin, but absence of atherosclerotic coronary disease. Shock was managed with intravenous administration of phenylephrine (n=6), norepinephrine (n=6), ß-blocker (n=7), and vasopressin (n=1). Mechanical circulatory support was required in 8, including intra-aortic balloon pump (n=4), venoarterial extracorporeal membrane oxygenation (n=3), and Impella and Tandem Heart in 1 each. In refractory shock, urgent relief of obstruction by myectomy was performed in 5, and alcohol ablation in 1. All patients survived their critical illness, with full recovery of systolic function. Conclusions When cardiogenic shock and LV ballooning occur in obstructive HCM, they are marked by distinctive anatomic and physiologic features. Relief of obstruction with targeted pharmacotherapy, mechanical circulatory support, and myectomy, when necessary for refractory shock, may lead to survival and normalization of systolic function.

Quality assurance of quantitative cardiac T1-mapping in multicenter clinical trials - A T1 phantom program from the hypertrophic cardiomyopathy registry (HCMR) study.

BACKGROUND: Quantitative cardiovascular magnetic resonance T1-mapping is increasingly used for myocardial tissue characterization. However, the lack of standardization limits direct comparability between centers and wider roll-out for clinical use or trials. PURPOSE: To develop a quality assurance (QA) program assuring standardized T1 measurements for clinical use. METHODS: MR phantoms manufactured in 2013 were distributed, including ShMOLLI T1-mapping and reference T1 and T2 protocols. We first studied the T1 and T2 dependency on temperature and phantom aging using phantom datasets from a single site over 4 years. Based on this, we developed a multiparametric QA model, which was then applied to 78 scans from 28 other multi-national sites. RESULTS: T1 temperature sensitivity followed a second-order polynomial to baseline T1 values (R2 > 0.996). Some phantoms showed aging effects, where T1 drifted up to 49% over 40 months. The correlation model based on reference T1 and T2, developed on 1004 dedicated phantom scans, predicted ShMOLLI-T1 with high consistency (coefficient of variation 1.54%), and was robust to temperature variations and phantom aging. Using the 95% confidence interval of the correlation model residuals as the tolerance range, we analyzed 390 ShMOLLI T1-maps and confirmed accurate sequence deployment in 90%(70/78) of QA scans across 28 multiple centers, and categorized the rest with specific remedial actions. CONCLUSIONS: The proposed phantom QA for T1-mapping can assure correct method implementation and protocol adherence, and is robust to temperature variation and phantom aging. This QA program circumvents the need of frequent phantom replacements, and can be readily deployed in multicenter trials.

The Mitral Valve in Obstructive Hypertrophic Cardiomyopathy: A Test in Context.

Mitral valve abnormalities were not part of modern pathological and clinical descriptions of hypertrophic cardiomyopathy in the 1950s, which focused on left ventricular (LV) hypertrophy and myocyte fiber disarray. Although systolic anterior motion (SAM) of the mitral valve was discovered as the cause of LV outflow tract obstruction in the M-mode echocardiography era, in the 1990s structural abnormalities of the mitral valve became appreciated as contributing to SAM pathophysiology. Hypertrophic cardiomyopathy mitral malformations have been identified at all levels. They occur in the leaflets, usually elongating them, and also in the submitral apparatus, with a wide array of malformations of the papillary muscles and chordae, that can be detected by transthoracic and transesophageal echocardiography and by cardiac magnetic resonance. Because they participate fundamentally in the predisposition to SAM, they have increasingly been repaired surgically. This review critically assesses imaging and measurement of mitral abnormalities and discusses their surgical relief.

Doppler Systolic Signal Void in Hypertrophic Cardiomyopathy: Apical Aneurysm and Severe Obstruction without Elevated Intraventricular Velocities.

BACKGROUND: In patients with hypertrophic cardiomyopathy (HCM), akinetic apical aneurysms are associated with ventricular tachycardia, heart failure, apical thrombus, and mortality. The cause of apical aneurysms remains unresolved, and there is controversy about prevalence and significance of mid-left ventricular (LV) obstruction, often present in these patients. The aim of this study was to test the hypothesis that low velocities in patients with aneurysms are due to near complete cessation of mid-LV flow, characteristically marked by a Doppler signal void. METHODS: This was a retrospective analysis of 39 patients with HCM with segmental hypertrophy of the mid left ventricle and complete systolic emptying at the mid-LV level. The severity of dynamic obstruction was evaluated by measuring the time during which cross-sectional mid-LV cavity area was <1 cm(2). Presence or absence of an LV Doppler midsystolic signal void was determined. RESULTS: Akinetic apical aneurysms were present in 21 patients. The duration of two-dimensional mid-LV short-axis complete emptying was longer in patients with akinetic apical aneurysms (194 ± 45 vs 148 ± 63 msec, P = .013), nearly 50% of systole. Midsystolic signal voids were seen only in patients with akinetic apical aneurysms (P < .001), present in 86%. In patients with akinetic aneurysms, there was a strong correlation between the duration of the systolic signal void and the proportion of systole with complete emptying < 1 cm(2) (r = 0.704; P = .001). Complete emptying < 1 cm(2) for ≥ 38% of systole was associated with akinetic aneurysm (odds ratio, 9.35; P < .004). CONCLUSION: Patients with akinetic apical aneurysm HCM have near complete cessation of flow across severe dynamic mid-LV obstruction for nearly 50% of systole. This explains how the adverse effects of obstruction may occur without high velocities on echocardiography.

Echocardiography before and after resect-plicate-release surgical myectomy for obstructive hypertrophic cardiomyopathy.

BACKGROUND: Anatomic features of obstructive hypertrophic cardiomyopathy are septal hypertrophy, elongated mitral leaflets, and anterior displacement of the papillary muscles. In addition to extended myectomy, the resect-plicate-release operation adds horizontal plication of the anterior mitral leaflet (AML) and release of the anterolateral papillary muscle (APM) in selected patients. The aim of this study was to test the hypotheses that (1) preoperative findings would be associated with procedures applied, (2) anatomic corrections would be observable postoperatively, and (3) there would be consistently good physiologic outcomes. METHODS: A retrospective study was conducted of patients with obstructive hypertrophic cardiomyopathy who had adequate echocardiograms before and 9.5 ± 12 months after the resect-plicate-release operation was performed from 2006 to 2012. RESULTS: Seventy-seven patients underwent myectomy, 50 AML plication, and 50 APM release. Patients who underwent plication had longer AMLs (32 ± 4 vs 28 ± 4 mm; P < .004). Anterior extension of the APM was more common with papillary muscle release (86% vs 62%, P < .04). Twenty-seven (35%) had septal thickness ≤ 18 mm; mitral valve-sparing operations were possible because of plication in 19 patients (70%), papillary release in 21 (78%), and one or both in 96%. Patients who underwent plication had decreased AML length by 16%, residual leaflet length by 33%, and protrusion by 24%. After APM release, there was decreased distance from mitral coaptation to the posterior wall. Surgery abolished severe systolic anterior motion and resting gradients and reduced mitral regurgitation. CONCLUSIONS: Echocardiographic AML length and directly observed slack provides a basis to recommend performance of plication and define its extent; plication decreases AML protrusion and stiffens the leaflet. Anterior APM recommends release, which drops the coaptation point posteriorly. Systematic relief of all aspects of obstructive pathophysiology results in consistent outcomes.

Symptomatic exercise-induced left ventricular outflow tract obstruction without left ventricular hypertrophy.

BACKGROUND: Left ventricular (LV) outflow tract obstruction (LVOTO) is most commonly seen in patients with hypertrophic cardiomyopathy. Postexercise dynamic LVOTO (DLVOTO) has been infrequently identified in symptomatic patients without LV hypertrophy, and its pathophysiology is not well established. The aim of this study was to identify echocardiographic abnormalities that might explain the dynamic development of systolic anterior motion, mitral-septal contact, and LVOTO in these patients. METHODS: Patients with DLVOTO and normal wall thickness were compared with 20 age-matched and gender-matched controls with normal stress echocardiographic findings. Two other groups were also compared: patients with DLVOTO and mild segmental hypertrophy (segmental wall thickness ≤15 mm) and patients with normal left ventricles but DLVOTO after dobutamine stress. RESULTS: Six symptomatic patients were identified (mean age, 48 ± 9 years; range, 37-60 years; five men) with normal wall thickness who developed DLVOTO after exercise during a 6-year period. Five had been hospitalized for cardiac symptoms. The mean postexercise LV outflow tract gradient caused by systolic anterior motion mitral-septal contact was 107 ± 55 mm Hg (range, 64-200 mm Hg). All patients had echocardiographic LV wall thicknesses in the normal range (≤12 mm). Structural abnormalities of the mitral valve were identified in all six patients. These were elongated posterior leaflets (2.0 vs 1.5 cm, P < .0005), elongated anterior leaflets (3.2 vs 2.6 cm, P = .015), increased protrusion height of the mitral valve beyond the mitral annular plane (2.6 vs 0.6 cm, P < .00001), and residual protruding portions of the mitral valve leaflets (0.85 vs 0.24 cm, P < .005). There was anterior positioning of the papillary muscles in the LV cavity, with a greater distance from the plane of the papillary muscles to the posterior wall (1.8 vs 1.3 cm, P = .03). In two patients, potentially provoking medications were stopped; two patients received ß-blockers, with reductions of angina. Medium-term prognosis was good; no patient had died after 3.5 years. The mitral valve abnormalities in the 10 patients with DLVOTO and mild segmental hypertrophy were qualitatively and quantitatively very similar to those in patients with DLVOTO without hypertrophy. In contrast, the valves of patients with dobutamine stress DLVOTO were not elongated, but 50% had residual mitral leaflets that protruded past the coaptation point by ≥5 mm. CONCLUSIONS: DLVOTO after exercise can occur in the absence of LV hypertrophy and may be associated with high gradients and cardiac symptoms. Elongated, redundant mitral valve leaflets with anterior position of the papillary muscles appear to cause the postexercise obstruction.

Treatment of obstructive hypertrophic cardiomyopathy symptoms and gradient resistant to first-line therapy with ß-blockade or verapamil.

BACKGROUND: There is controversy about preferred methods to relieve obstruction in hypertrophic cardiomyopathy patients still symptomatic after ß-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 ß-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.

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 ß 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.

Demonstration of left ventricular outflow tract eccentricity by real time 3D echocardiography: implications for the determination of aortic valve area.

BACKGROUND: Determination of the left ventricular outflow tract cross-sectional area (ALVOT) is necessary for calculating aortic valve area (AVA) by echocardiography using the continuity equation (CE). In the commonly applied form of CE, pir(2) is used to estimate ALVOT utilizing the assumptions that LVOT is round and the parasternal long axis (PLAX) plane bisects LVOT. Imaging LVOT using real time 3D echocardiography (RT3DE) eliminates the need for these assumptions. We tested the hypothesis that LVOT is round based on a formula for eccentricity. METHODS AND RESULTS: In 53 patients, 2D echocardiography (2DE) and RT3DE were acquired. ALVOT was calculated by 2DE using pir(2) (ALVOT-2D). Using RT3DE, ALVOT planimetry was performed immediately beneath the aortic valve (ALVOT-3Dplan). Eccentricity Index (EI) was calculated using the shortest and longest LVOT diameters. The long axis was measured to be larger by 0.53 cm +/- 0.36 (P < 0.005). The median EI was 0.20 (0.00-0.54), indicating that half the subjects had at least a 20% difference between the major and minor diameters. ALVOT-3Dplan was larger than ALVOT-2D (3.73 +/- 0.95 cm(2) vs. 3.18 +/- 0.73 cm(2); P < 0.001) by paired analysis. Using the equation of an ellipse (piab), ALVOT-3Dellip was 3.57 +/- 0.95 resulting in improved agreement with ALVOT-3Dplan. CONCLUSIONS: In our small patient sample with normal aortic valves, we showed the LVOT shape is usually not round and frequently, elliptical. Incorrectly assuming a round LVOT underestimated the ALVOT-3Dplan and consequently the AVA by 15%. Investigating the LVOT in aortic stenosis is warranted to evaluate whether RT3DE may improve measurement of AVA.