[Predictive value of the shunt-to-infarct size ratio as a surgical risk factor in patients with decompensated post-ischemic interventricular septal rupture].

Postischemic septal rupture has always been evaluated, in respect of surgical indication, as regards the time lapse between infarct and rupture, interval between rupture and operation, extension of myocardial damage and general risk factors such as age, sex and associated pathologies. But in fact the surgeon is dealing with a two sided problem, the MI and the rupture, and thus surgical results depend upon both the residual ventricular function after MI and the consequences of volume overload on a damaged muscle. Surgical indication could not be based on a single criterion only. Extension of the MI alone is not fully predictive of operative mortality because, aside the reperfusion injury, the repair further jeopardizes viable myocardium and alters ventricular geometry; although the shunt appears unrelated to mortality it certainly interferes with operative outcome at least because of the time elapsed between rupture and repair. So far an index which could correlate the extension of myocardial damage and the entity of the shunt with each other was not available. Patients with septal rupture follow an emergency protocol and are often insufficiently investigated but every patients has a least one echo-Doppler evaluation or even a ventriculography while one or more ECGs are always available. With the presumption that the Qp/Qs is roughly indicative of the right ventricular volume overload and that ecg signs of myocardial infarct are always reliable, we have reviewed among our 24 patients with septal rupture those where a full ecg tracing and a quantitative Echo or angiographic evaluation of the shunt were available.