Miocardiopatia HipertróficaMiocardiopatia Hipertrófica

Valor del ecocardiogramaValor del ecocardiograma

Sociedad de Cardiología de Tucumán

26 de Octubre 2006

Dr. Enrique Alonso

Miocardiopatia HipertróficaMiocardiopatia Hipertrófica

Valor del ecocardiogramaValor del ecocardiograma

• Diagnóstico

• Pronóstico

• Tratamiento

Hypertrophic Cardiomyopathy

Left ventricular hypertrophy, symmetric or asymmetric, in absence of other heart or systemic disease, which can provoke left ventricular hypertrophy

Echocardiography for Diagnosis

• Pattern and extent of hypertrophy

• Presence and degree of left ventricular outflow tract obstruction

• Systolic anterior motion (SAM) of the mitral apparatus

Hypertrophy: May involve any and all portions of the left and right ventricle in the small

ventricular cavity and normal left ventricular systolic function.Typical example of asymmetric left ventricular hypertrophy. Septal thickness (>15mm) at least 1.3-1.5 times the thickness of the posterior wall. Concentric hypertrophy in < 10% of cases.

Hypertrophic cardiomyopathy type III: Parasternal short-axis view showing severe

asymmetric hypertrophy in septal and lateral segments.

Left Ventricular Outflow Tract ObstructionMultifactorial mechanisms:

narrowing of outflow tract

anterior displacement of mitral apparatus

hyperdynamic systolic function

Venturi-like effect to pull the mitral valve apparatus into the left ventricular outflow.

Systolic Anterior Motion of Mitral Valve ApparatusThe M-mode permits a more precise assessment of the

different degrees of mitral valve anterior systolic movement (arrows).

The magnitude and duration of SAM are related to the outflow obstruction systolic anterior motion. It is not pathognomonic of HCM. Hypercontractile states may buckle the chordae tendinae rather than the mitral valve leaflet

Parasternal Long-Axis View

M-mode showing SAM and asymmetric hypertrophy (septum /PW 1.8)

Anterior systolic movement of mitral valve.

Longitudinal parasternal view showing the anterior systolic movement of the mitral valve in contact with the interventricular septum.

Doppler Technique is Fundamental:• to assess the presence of left ventricular and / or mesoventricular outflow tract

dynamic obstruction • to quantify mitral insufficiency • to rule out fixed aortic valvular or subvalvular stenosis Representative Diagram of Different Flows in Obstruction Hypertrophic

Cardiomyopathy:• dynamic obstruction flow in left ventricular outflow tract with predominantly

systolic increased velocity • mitral insufficiency flow • normal velocity aortic valve flow with rapid acceleration and meso-telesystolic

deceleration.

•

A displacement of the leaflets may also lead to relative non-coaptation and produce mitral regurgitation. Typically, the jet of mitral regurgitation is directed laterally or posteriorly away from the SAM. In a non-posterior jet of MR, independent intrinsic mitral valve disease should be considered.

Dynamic Subvalvular GradientContinuous Doppler from apical view of LVOT with

maximum velocity in telesystole of 6 m/sec, which permits the calculation of a maximum dynamic gradient of 152 mmHg.

Dynamic Subvalvular GradientWhen signs of dynamic obstruction are not evident in basal conditions, it

is possible on occasions to provoke them (hypertrophic myocardiopathies with latent or provokable obstruction) by manoeuvres that accentuate the pressure gradient:

• amyl nitrite inhalation

• physical exercise

• Valsalva manoeuvre

• isoprenalin perfusion

Indice de desaceleración medio septal- TDI

Relacion con HCM obstructiva:

IDMseptal, asociado al 58% con obstrucción al TSVI

Asociado a gradientes de 30 mmHg – sensibilidad 93 % especifidad 91 %

Util en imágenes dificultosas ( test Ejercicio) y en insuficiencia mitral

Breithardt y Col Heart 2005; 91 : 379-380

Figure 1  ECG invasively measured left ventricular outflow tract (LVOT) pressure gradient and the tissue Doppler imaging (TDI) velocity trace from the basal septum. Note the simultaneous development of the LVOT gradient (open arrow) and the mid systolic septal deceleration notch (solid arrow). Adapted from Breithardt and colleagues.3

Assessment of Systolic and Diastolic Left Ventricular Function

Systolic function is normal or hyperdynamic. However, tissue Doppler assessment shows an abnormal longitudinal shortening in established HCM or family members with similar genetic defects. Increasing muscle mass and abnormal fibrosis provoke left ventricular stiffness and variable assessment of degrees of diastolic dysfunction.Conventional Doppler indices have not been helpful in assessing diastolic function. Newer markers like tissue Doppler of mitral annular motion (early peak = e´) have proved to be far more discriminating in the assessment of the left ventricular (LV) filling pressures in HCM. A high ratio E/e´ is indicative of a high filling pressure in the left ventricle. Mitral septal systolic velocities are also decreased.

Función diastolica Regional y su impacto en la función diastolica global

FLUJO MITRAL

ECO M - COLOR

STRAIN RATE

K Goto JASEcho Julio 2006 vol 19 I 7

Función Diastolica Regional

El mecanismo mas importante de disfunción Diastolica Global en HCM, son las anormalidades de relajación Regional mas pronunciada en miocardio hipertrófico

Asincronia Diastolica

Índice de velocidad de relajación Diastolica temprana ( ERS) es mas sensitivo.

K Goto JASEcho julio 2006

Disfunción sistólica en HCM

Marcadores Ecocardiograficos:

Poco frecuente

Hipertrofia masiva: (p= 0,04), vulnerable a remodelación, por isquemia, cambios neurohormonales y hemodinámicas

Análisis multivariado DSVI, fue un fuerte predictor

DSVI tubo valor predictivo +, sensibilidad y especificidad baja.

R Thaman Heart 2005; 91 – 920 - 925

Función sistólica HCM

Strain 2D Dimensional:

Anormalidades sistólicas, subclínicas son detectadas precozmente con esta técnica

K Serni y Col JAAC vol 47, Issue 6- ;Marzo 2006

Echo in Management of HCMCare must be taken to reduce variability in gradient changes after

pharmacotherapy, dual chamber pacing, septal ablation and surgical myectomy. Myocardial contrast echo can be used to identify the vascular distribution of individual septal perforating branches of the left anterior descending artery. This is important for correct alcohol septal ablation. Observe a dynamic gradient of 92 mmHg.

Valor pronostico del diámetro de AI

Registro Italiano de HCM:

Diámetro de AI > 48 mm, tiene un valor predictivo independientemente de FA con obstrucción en TSVI, pronostico de muerte relatado a insuficiencia cardiaca

Sinistri y col – AJ of Cardiology vol 98 –I 7 – 2006 octubre

Incidencia de Muerta Súbita

Hipertrofia masiva

100

60

40

20

< 30 30 – 59 >60

P. Sorafja JASEcho junio 2006 vol 1 I 6

Hipertrofia Masiva

Mortalidad

2, 3 % Anual

Evaluación del Tratamiento

Marcapaso DDD y su impacto en el gradiente TSVI

70 % pac. – intima relación entre modificación del marcapaso (AVI) y reducción gradiente

Gradiente pico TSVI se redujo en 92% de los pac.

92% pacientes mejora clase funcional

Topilsk y col Am J of Cardiology vol 97, I12- 2004

Muchas Gracias

Dr. Enrique Alonso