Miocardiopatía chagásica

Dr. José Milei

VI Cátedra de Medicina Interna – Hospital de Clínicas – UBA

Director del Instituto de Investigaciones Cardiológicas (ININCA) UBA-CONICET

•Miocarditis crónica más frecuente del mundo•Enfermedad parasitaria que más muertes causa en Latino América según la OMS.•La enfermedad de Chagas continúa siendo un riesgo para la salud de aproximadamente 28 millones de personas, la mayoría latinoamericanos (OMS, 2005)

ClasificaciónClasificación de la Miocardiopatía Chagásica Crónica 113

Grupo Hallazgos

I

Serología PositivoSíntomas Asintomático

ECG NormalRadiografía de tórax Normal

II

Serología PositivoSíntomas Sin evidencia de ICC

ECG

A: alteraciones de condución

B: Arrítmias ventricularesC: Ambas ( A + B)

Radiografía de Tórax Diámetro < 0.55

III

Serología PositivoSíntomas Evidencia de ICC

ECG Patológico

Radiografía de TóraxCardiomegalia. Diámetro >

0. 55Storino RA, Milei J et al, Clasificación Clínica de la miocardiopatía chagásica crónica e historia natural. Medicina (Bs. As) 1985;63:160

• Una disociación A-V con unas ondas P claramente distinguibles e

independientes de un ritmo QRS.

• Ondas P asociadas con complejos QRS alternantes que se

identifica mejor en la derivación V1, se debe a un bloqueo

retrógrado 2:1.

• Una relación de tipo 1:1 entre ondas P y los complejos QRS, con

un intervalo RP corto.

• Disociación A-V, un impulso sinusal adecuadamente sincronizado

de forma fortuita puede fusionarse con un complejo QRS ancho

debido a la TV y producir un único ciclo de un complejo QRS

alterado (habitualmente estrechado).

• Una duración del complejo QRS mayor de 0.14 segundos, como

causa de la taquiarritmia con complejos QRS anchos.

• Complejos QRS coincidentemente positivos o negativos a lo

largo de las derivaciones precordiales desde V1 a V6.

Pericardial effusion in chagasic myocarditis

Apical aneurysm

Diagnóstico diferencial entre la ChrChC y DCM *

Clinical StudiesChronic Chagasic Cardiomyopathy

Primary Idiopathic Dilated

CardiomyopathySerology for T. cruzi Positive NegativeMean age 48 40Clinical Findings NYHA Class II 26% 60% Symptom that

predominatesDyspnea 64% Dyspnea 100%

ECG findings RBBB + LAFBLBBB or incomplete

LBBB Afib or Aflutter 2% 26%Chest x-ray with cardiomegaly

Extreme 10% Extreme: 53%

Holter monitoringPVC: 48%SB: 28%

PVC: 50%Afib: 33%

Heart Sounds

High pitched holosystolic murmur:

46%S3: 31%

High pitched holosystolic murmur:

58%S3: 75%

Echocardiogram Left ventricular

dilatation87% 100%

Left ventricular diastolic diameter

63 mm 67 mm

Ventricular Aneurysm 30% 0%

Gamma CameraRegional hypokinesia

38%Global Hypokinesia

54%

Need of Pacemaker13% for trifascicular

block13% for 3° AV block

Annual Mortality5.2% (17% for 5 year

mortality)13%

* Storino RA, Milei J. Enfermedad de Chagas. Buenos Aires: Mosby-Doyma; 1994

Progresión de la enfermedad

Storino RA, Milei J et al. Enfermedad de Chagas: Doce años de seguimiento en área urbana. Revista Argentina de Cardiología 1992;60:205-216

Tratamiento del Chagas Crónico*Author (year)

CountryMaterial and

MethodOutcome of treated group Conclusion

de Andrade et al94 (1996)Brazil

129 seropositive children from 7 to 12 years old (resulted from screening of 1990 schoolchildren)64 treated with benznidazole. 65 untreated

Negative seroconversion in 55.8% Authors recommend the treatment of seropositive children.

Sosa Estani et al 95 (1998)Argentina

106 children from 6 to 12 years old 55 treated with Bz for 60 days51 untreated

Negative serconversion in 62%4.7% of the treated group had a positive xenodiagnosis versus a 51.2% in the placebo group.

Infected children may successfully be treated with Bz.

Lauria Pires et al92 (2000) Brazil

91 Chagasic patients41 uninfected patients

100% of treated patients showed presence of the parasite by PCR. Not significant difference in between treated and untreated patients concerning ECG alterations and parasitemia levels.

Treatment of chronic Chagas with nitroderivatives is unsatisfactory and cannot be recommended

Cançado 86 (2002)Brazil

21 acute chagasic patients113 chronic chagasic patients

Cure in 8% of chronic chagasic patients and 76% of acute cases.

Authors consider that Bz should be used in the treatment of chronic patients.

Reyes et al 90 (2005)

Review of the literatureConsidered a single double blind randomized clinical trial and 5 case control or case series.

Treatment of chronic Chagas with these drugs is not sufficiently well supported.

García et al 89 (2005)

8 infected mice8 infected mice treated with Bz18 healthy mice

Decrease in the parasite loadDecrease in ECG alterationsDecrease in myocarditis

Authors emphasize the importance of Bz in chronic chagasic patients in order to decrease or retard the development of ChrChC.

Viotti et al 93 (2006)Argentina

566 patients from 30 to 50 years old283 treated for 30 days with Bz283 untreated

15% negative seroconversion Significantly less progression to the disease (p0.002) and ECG alterations (p0.001) than the untreated group.

Bz treatment is associated with a reduced risk for progression of ChrChC.

Fabbro et al 88 (2007) Argentina

Total 111 patients.57 untreated.54 treated.Santa Fe (Argentina)

37% seroconversion (cured)27.8% decreased titers35.2% remained positive with constant titersFavorable clinical evolution in the treated group

This study favors the treatment of chronic Chagas disease.

Bern et al (2007) United States

Review of the literature Refer to text

CONCLUSION 1Treatment should always be offered (strength of

recommendation graded A) in acute T cruzi

infection, in early congenital T cruzi infection,

children up to 18 years old with chronic T cruzi

infection and in reactivated T cruzi infection in

patients with HIV/AIDS or other immunosupression.

Bern C, et al. Evaluation and Treatment of Chagas Disease in the United States. JAMA

2007;298(18):2171-81

CONCLUSION 2• Treatment must be discouraged in chronic chagasic

cardiomyopathy because of the low chance of parasitological and serological cure, with dubious clinical benefits and intense side effects.

• Lack of randomized controlled clinical studies • An important issue is the difficulty in evaluating the

effectiveness of treatment, as the infection is very complex itself.

• It “would be” of utmost importance to conduct further studies to solve the controversy, employing non-invasive methods to better understand the cardiovascular status in chagasic patients and PCR methods to establish (or not) parasitological cure.

Milei J. Treatment of chronic Chagas’ disease with current anti-parasitic drugs. World Congress of Cardiology 2008