Value of electrocardiogram in diagnosing right ventricular involvement in patients with an acute inferior wall myocardial infarction.

Abstract

To study the value of the electrocardiogram in diagnosing right ventricular involvement in acute inferior wall myocardial infarction, the electrocardiographic findings were analysed in 67 patients who had had scintigraphy to pinpoint the infarct. All 67 patients were consecutively admitted because of an acute inferior wall infarction. A 12 lead electrocardiogram with four additional right precordial leads (V3R, V4R, V5R, and V6R) was routinely recorded on admission and every eight hours thereafter for three consecutive days. Thirty-six to 72 hours after the onset of chest pain a 99mtechnetium pyrophosphate scintigraphy and a dynamic flow study were performed to detect right ventricular involvement, which was found in 29 of the 67 patients (43%). ST segment elevation > 1 mm in leads V3R, V4R, V5R, and V6R is a reliable sign of right ventricular involvement. ST segment elevation , 1 mm in lead V4R was found to have the greatest sensitivity (93%) and predictive accuracy (93%). The diagnostic value of a QS pattern in lead V3R and V4R or ST elevation > 1 mm in lead V1 was much lower. ST segment elevation in the right precordial leads was short lived, having disappeared within 10 hours after the onset of chest pain in half of our patients with right ventricular involvement. When electrocardiograms are recorded in patients with an acute inferior wall infarction within 10 hours after the onset of chest pain, additional right ventricular infarction can easily be diagnosed by recording lead V4R.

Right Ventricular Function Suffers From Reperfusion Delay: Tissue Doppler Study

“…1 Routine early diagnostics used for RVMI detection rely on electrocardiogram and standard echocardiographic recordings. 2,3,4 Considering that in patients with RVMI the risk of serious complications and death are significantly increased 5,6,7 the assessment of RV systolic function is an important challenge. Tissue Doppler echocardiography (TDE) has proven to be a simple and reproducible marker of RV function which significantly correlates with the right ventricular ejection fraction assessed by first-pass radionuclide ventriculography and magnetic resonance imaging.…”

Diretrizes

“…Esse achado pode ser transitório: em 50% dos pacientes, desaparece após dez horas do início dos sintomas 378 . É fundamental que a equipe multidisciplinar envolvida no atendimento esteja treinada para o registro dessa derivação, que deve ser realizado em todos os pacientes com infarto inferior na admissão hospitalar.…”

III Diretriz sobre tratamento do infarto agudo do miocárdio

“…Este achado pode ser transitório: em 50% dos pacientes, desaparece após 10h do início dos sintomas 518 . É fundamental que a equipe multidisciplinar envolvida no atendimento esteja treinada para o registro desta derivação, que deve ser realizado em todos os pacientes com infarto inferior na admissão hospitalar.…”