[Acute right ventricular myocardial infarct. New diagnostic and therapeutic approaches in a prognostically unfavorable disease picture].

BACKGROUND

Acute inferior myocardial infarction frequently involves the right ventricle (RV). However, very little is known on the prognostic impact of RV involvement in the in-hospital and longterm course, as well as on reliable diagnostic strategies to identify RV infarction early after admission.

PATIENTS AND METHODS

In 200 consecutive patients with acute inferior myocardial infarction, we assessed on admission the prevalence and diagnostic accuracy of ST elevation in lead V4R to determine RV involvement, as well as its prognostic implications for in-hospital complications, early and late mortality and the benefit of thrombolytic therapy. Follow-up period was one to six years (mean +/- SD, 37 +/- 12 months).

RESULTS

In-hospital mortality after inferior myocardial infarction was 19%, major complications occurred in 47% of patients. Presence of ST-segment elevation in V4R in 107 patients (54%) was highly predictive of RV infarction (sensitivity: 88%, specificity: 78%, diagnostic efficiency: 83%) and increased the in-hospital mortality rate from 6% to 31% (p < 0.0001) and major in-hospital complications from 28% to 64% (p < 0.0001). Cox regression analysis showed ST elevation in V4R to be independent of and superior to all other clinical variables available at the time of admission (additional risk for in-hospital mortality: 7.7; for major complications: 4.7). Thrombolysis was associated with a reduced mortality (3.7 times, p < 0.0005) and complication rate (2.4 times, p < 0.0001) only in patients with RV infarction. Post-hospital course was similar in patients with and without RV infarction.

CONCLUSIONS

RV involvement during acute inferior myocardial infarction, accurately diagnosed by ST-segment elevation in V4R, is a strong, independent parameter for mortality and major in-hospital complications and may help to identify patients who will benefit most from thrombolytic therapy. Electrocardiographic assessment of RV infarction should be routinely performed in all patients admitted with acute inferior myocardial infarction.