Systolic anterior motion begins at low left ventricular outflow tract velocity in obstructive hypertrophic cardiomyopathy

Sherrid, Mark V.; Gunsburg, David Z.; Moldenhauer, Sonja; Pearle, Gretchen

doi:10.1016/s0735-1097(00)00830-5

Cited by 254 publications

(145 citation statements)

References 37 publications

Supporting

Mentioning

131

Contrasting

Unclassified

Order By: Relevance

“…However, subsequent studies have shown that accelerated flow around the septum produces a drag effect on an elongated and displaced mitral valve apparatus to ''push'' the leaflets into the outflow tract. 21,22 The dynamic nature of LVOT obstruction results from an amalgamation of changes in ventricular loading conditions and myocardial contractility that are sensitive to fluctuations in volume status, autonomic nervous activity, diurnal variation, pharmacotherapy, exercise, and even physical positioning during gradient assessment. 4,23 -26 The recognition of the variability of LVOT outflow tract gradient in clinical practice is lacking.…”

Section: Discussionmentioning

confidence: 99%

Left Ventricular Outflow Tract Gradient Variability in Hypertrophic Cardiomyopathy

Geske

Sorajja

Ommen

et al. 2009

Clinical Cardiology

View full text Add to dashboard Cite

Background:The presence and magnitude of left ventricular outflow tract (LVOT) obstruction directs the management algorithm in symptomatic patients with hypertrophic cardiomyopathy (HCM). Although it is well known that the degree of LVOT obstruction is dynamic and dependent upon ventricular load and contractility, the magnitude and potential impact of the day-to-day variability seen in practice has not been well appreciated. Hypotheses: We hypothesized that LVOT gradient variability in HCM has an impact on clinical decision-making. Methods: A total of 100 HCM patients (mean age, 58 ± 13 years; 47% male) underwent comprehensive 2-dimensional Doppler transthoracic echocardiography and cardiac catheterization with transseptal measurement of left-sided pressures. All studies were performed within 48 hours of one another. Results: The correlation of LVOT gradients from both methods performed at different times had a wide scatter with the 95% confidence limits of agreement being ±84 mm Hg. For classifying patients as having severe LVOT obstruction on the basis of either method (<30 vs ≥30 mm Hg), discrepant results occurred in 21% of patients. To confirm the accuracy of Doppler measurements, 15 studies were performed with simultaneous measurement of LVOT gradient, which revealed a very strong correlation (r = 0.98, p < 0.0001) with 95% confidence limits of agreement ±12 mm Hg. Conclusions: In patients with HCM, LVOT gradient measurements are routinely obtained to characterize the severity of obstruction. However, these data demonstrate the marked variability of the LVOT obstruction, which must be considered when determining appropriate therapy in symptomatic patients.

show abstract

Section: Discussionmentioning

confidence: 99%

Left Ventricular Outflow Tract Gradient Variability in Hypertrophic Cardiomyopathy

Geske

Sorajja

Ommen

et al. 2009

Clinical Cardiology

View full text Add to dashboard Cite

show abstract

“…Through two-dimensional echocardiography, the SAM was revealed to begin before ejection, and slightly differentiated from the Venturi effect 16 . The obstruction is truly determined by the complex interaction between septum, mitral valve and flow vectors generated in ventricular cavity.…”

Section: Introductionmentioning

confidence: 99%

“…The position of the mitral valve leaflets in relation to the outflow tract is fundamental for the obstruction to develop 16 . The anterior displacement of papillary muscles and mitral subvalvar apparatus change the outflow tract geometry, reducing the respective area, favoring the contact between the anterior leaflet and the septum 19 .…”

Section: Introductionmentioning

confidence: 99%

“…In 30% of the cases with obstruction, there are complex deformities involving the mitral valve, such as anterior and/or posterior leaflet lengthening, or even direct implantation in papillary muscles, which can obstruct the outflow tract 24 . In these cases, the mitral valve coaptation point may be displaced anteriorly and be placed along the leaflets, and not on their borders 16 . The anterior leaflet lengthening associated with low-diameter outflow tract is connected to gradient increase 24 .…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

O diagnóstico da obstrução da via de saída do ventrículo esquerdo na cardiomiopatia hipertrófica

Mattos¹,

Torres²,

Rebelatto³

et al. 2012

Arq. Bras. Cardiol.

View full text Add to dashboard Cite

Hypertrophic cardiomyopathy is a prevalent genetic disease characterized by left ventricular hypertrophy, presenting dynamic obstruction of outflow tract with subaortic gradient happening at rest in 30% of the cases. It is attributed to the intricate interaction between the anterior mitral leaflet, the interventricular septum and altered flow vectors generated in left ventricle along with changes in outflow tract geometry. Mitral regurgitation in varying degrees is found with or without association with structural deformities of the valve apparatus. The exercise echocardiogram evidences latent obstruction easily induced by exercise in 60 to 75% of nonobstructive forms. The determination of the gradient under this condition must be considered in routine investigation of patients with mild or no obstruction at rest. The evaluation of hypertrophic cardiomyopathy incorporates methods based on the ultrasound image, which, along with MRI, allow recognizing ventricular obstruction generating mechanisms, thus facilitating the diagnosis and management of obstructive and latent obstructive forms.

show abstract

“…12,13) Possible explanations for this paradox include real observation of true hypercontractility in this disease entity, pseudo-normal contractility under the decreased left ventricular (LV) radial wall stress as a result of compensatory remodeling, 14,15) pseudo-vigorousness by favorable afterload reduction with complication of mitral regurgitation due to outflow obstruction, [16][17][18][19] or other unknown mechanisms.…”

mentioning

confidence: 99%

Focalized Contractile Impairment at Hypertrophied Myocardium Proven in Consideration of Wall Stress in Patients With Hypertrophic Cardiomyopathy

et al. 2006

View full text Add to dashboard Cite

SUMMARYIn hypertrophic cardiomyopathy (HCM) a hyperkinetic state is sometimes observed in spite of impaired systolic function in the hypertrophied myocardium. The aim of the present study was to determine the mechanism of this paradox.Seventeen patients with HCM and 10 normal subjects underwent cine magnetic resonance (MR) imaging to measure percent systolic wall thickening and percent fractional shortening. The ratio of systolic radial wall stress of the LV at the hypertrophied myocardium over that at the nonhypertrophied myocardium was evaluated to describe the focal advantageous condition for wall thickening.The ratio was 0.66 ± 0.36 at the start of contraction and 0.78 ± 0.31 at early-systole, indicating consistently smaller radial wall stress at the hypertrophied myocardium. Although the condition for contraction was favorable (a ratio less than 1.00), percent systolic wall thickening at the hypertrophied myocardium (23.0 ± 11.8%) was smaller than that at the nonhypertrophied myocardium (70.5 ± 32.3%). Smaller end-diastolic dimension (HCM group; 45.2 ± 4.2 mm, reference group; 48.9 ± 4.1 mm, P = 0.04) with a statistically identical value of systolic decrease in intraventricular dimension (HCM group; 19.7 ± 3.9 mm, reference group; 18.9 ± 3.2 mm, P = 0.60) yielded high percent fractional shortening in patients with HCM (43.5 ± 7.6%).Although contractile impairment was proven at the hypertrophied region with low radial wall stress in the HCM group, the smaller end-diastolic dimension in this group resulted in high percent fractional shortening. (Int Heart J 2006; 47: 247-258)

show abstract

Systolic anterior motion begins at low left ventricular outflow tract velocity in obstructive hypertrophic cardiomyopathy

Cited by 254 publications

References 37 publications

Left Ventricular Outflow Tract Gradient Variability in Hypertrophic Cardiomyopathy

Left Ventricular Outflow Tract Gradient Variability in Hypertrophic Cardiomyopathy

O diagnóstico da obstrução da via de saída do ventrículo esquerdo na cardiomiopatia hipertrófica

Focalized Contractile Impairment at Hypertrophied Myocardium Proven in Consideration of Wall Stress in Patients With Hypertrophic Cardiomyopathy

Contact Info

Product

Resources

About