[The treatment of hypertrophic obstructive cardiomyopathy refractory to medical treatment by DDD pacing].
OBJECTIVE
In spite of medical treatment, 10% of patients with hypertrophic obstructive cardiomyopathy remain symptomatic, needing surgical treatment. Recent evidence suggests that sequential atrio-ventricular pacing may improve the hemodynamic and clinical situation.


METHODS
We studied 10 patients with hypertropic obstructive cardiomyopathy (6 women), aged 37-76 years (X = 62 +/- 12) with dyspnea and/or angina, in functional class IV (7) or III (3) of the New York Heart Association. Hemodynamic study was performed basaly and during atrio-ventricular pacing with atrio-ventricular intervals ranging from 75% of basal PR to 50 ms. A DDD pacemaker was implanted in 9 cases, the remainder was treated surgically.


RESULTS
The pressure gradient was reduced from 105 +/- 32 to 40 +/- 35 mmHg (p < 0.001); end-diastolic left ventricular pressure fell from 22 +/- 4 to 13 +/- 8 mmHg (p < 0.01), systolic aortic pressure rose from 107 +/- 24 to 125 +/- 13 mmHg (p < 0.05) and cardiac output increased from 3.6 +/- 1.1 to 4.1 +/- 0.81/m (p < 0.05). Mitral insufficiency decreased in 5 of 6 cases, notably in 2 improving from 4+ to 1+. After 1-20 months (X = 10 +/- 6) the 9 patients treated with a permanent DDD pacemaker are in functional class I (7 cases) or II (2 cases).


CONCLUSIONS
Atrio-ventricular pacing hypertrophic obstructive cardiomyopathy reduces the systolic gradient and left ventricular end-diastolic pressure with an increase in cardiac output and aortic pressure and improves mitral insufficiency. Short-mid term follow up shows sustained clinical improvement. Optimal atrio-ventricular interval should be individualized.
Tascón
J
J
Servicio de Cardiología, Hospital Universitario 12 de Octubre, Madrid.
Albarrán
A
A
Pérez-Carasa
M A
MA
Andreu
J
J
Rodríguez
J
J
Coma
R
R
Cosío
F G
FG
D000208:Acute Disease; D000328:Adult; D000368:Aged; D006328:Cardiac Catheterization; D002304:Cardiac Pacing, Artificial / Q000379:methods* / Q000706:statistics & numerical data; D002312:Cardiomyopathy, Hypertrophic / Q000175:diagnosis / Q000503:physiopathology / Q000628:therapy*; D015150:Echocardiography, Doppler; D005260:Female; D006439:Hemodynamics; D006801:Humans; D008297:Male; D008875:Middle Aged; D010138:Pacemaker, Artificial
Tratamiento de la miocardiopatía hipertrófica obstructiva refractaria al tratamiento médico con estimulación DDD.