Role of right-sided chest leads in the detection of multivessel coronary artery disease in patients with extended Q-wave anterior myocardial infarction

ST-segment elevation of right precordial lead (V4 R) is associated with multivessel disease and increased in-hospital mortality in acute anterior myocardial infarction patients

BACKGROUND

ST segment elevation of chest lead V4 R is associated with worse prognosis in acute inferior ST-elevation myocardial infarction (STEMI). This study tried to determine the relationship between ST elevation in the right precordial lead V4 R and acute anterior STEMI.

METHODS

Prospective study of 144 consecutive anterior STEMI patients: all had 15-lead ECG recordings (12 conventional leads and V3 R-V5 R) obtained. Patients were classified into two groups on the basis of presence (Group I, 50 patients) or absence (Group II, 94 patients) of ST-segment elevation ≥0.5 mm in lead V4 R.

RESULTS

Multivessel involvement was significantly higher in Group I compared with Group II (54% and 23% respectively, P < 0.001). Major adverse cardiac events and in-hospital mortality was also significantly higher for those in Group I (P < 0.02 for both). A significant correlation was found between in-hospital mortality and those in Group I (P = 0.03, OR: 6.27, CI: 1.22-32.3). There was an independent relationship between in-hospital mortality and V4 R-ST elevation (P = 0.03, OR: 11.64, CI: 1.3-27.4).

CONCLUSION

ST segment elevation in chest lead V4 R is associated with multivessel disease and increased in-hospital mortality in patients with anterior STEMI that had undergone primary percutaneous coronary intervention to the left anterior descending artery.

The significance of right-sided chest leads in exercise testing for the detection of right ventricular dysfunction post myocardial infarction of the inferior wall

BACKGROUND

The incorporation of right-sided chest leads (V(3)R-V(5)R) into the standard exercise testing has been reported to improve its diagnostic accuracy. The purpose of this study was to evaluate the ability of exercise testing in detecting right ventricular (RV) dysfunction post myocardial infarction (MI) of the inferior wall, using additional V(3)R-V(5)R leads.

METHODS

We studied 133 patients (59 ± 5 years, 81 males) with a history of inferior MI due to right coronary artery obstruction (affirmed with coronary angiography). All patients underwent an echocardiographic assessment of RV function 4 weeks after discharge and an exercise treadmill test in order to detect possible RV dysfunction. Recordings during exercise were obtained with the standard 12 leads plus V(3)R-V(5)R.

RESULTS

From 133 patients, 97 (group A) presented with normal right ventricle according to the echocardiographic study while the rest 36 patients (group B) presented with RV dysfunction. Maximal exercise-induced ST-segment deviation (in mm) was similar in the standard 12 leads for the 2 groups (2.1 ± 0.4 vs 1.8 ± 0.3, p = NS) while in V(3)R-V(5)R it was greater in group B (0.7 ± 0.3 vs 1.4 ± 0.4, p<0.05). Sensitivity, positive prognostic value, negative prognostic value and accuracy of exercise testing in detecting RV dysfunction were all improved using V(3)R-V(5)R (78 vs 47%, 39 vs 29%, 87 vs 75%, 62 vs 55% respectively, p<0.05 for all) while specificity was not deteriorated (56 vs 58%, p = NS).

CONCLUSIONS

The addition of right-sided chest leads (V(3)R-V(5)R) improves the diagnostic ability of standard exercise testing in detecting and especially in excluding RV dysfunction post inferior MI.

Right-sided chest leads in exercise testing for detection of coronary restenosis

BACKGROUND

The incorporation of right-sided chest leads (V(3)R through V(5)R) into standard exercise testing has been reported to improve its diagnostic utility.

HYPOTHESIS

The purpose of this study was to evaluate any improvement in the ability of exercise testing in detecting restenosis, using additional V(3)R through V(5)R leads, in asymptomatic patients undergoing percutaneous coronary intervention (PCI) in the right coronary artery (RCA) or/and left circumflex (LCX).

METHODS

We studied 172 consecutive patients (54 +/- 7 years old, 106 males) undergoing PCI in RCA or/and LCX. A treadmill test had been performed before PCI. Six months later, all patients underwent a second treadmill test and arteriography in order to detect silent ischemia due to restenosis. Recordings during exercise were obtained with the standard 12-leads plus V(3)R through V(5)R.

RESULTS

Out of 172 patients, 106 had stenosis in RCA, 35 in LCX, and 31 in both vessels while 6 months later, restenosis was detected in 8 (for RCA), 3 (for LCX), and 3 (for both vessels) patients respectively. Sensitivity, specificity, positive prognostic value, negative prognostic value, and accuracy of exercise testing performed post PCI were ameliorated using V(3)R through V(5)R (79% vs 57%, 97% vs 80%, 69% vs 21%, 98% vs 95%, and 95% vs 78% respectively, P < .05 for all except negative prognostic value). Maximal exercise-induced ST-segment deviation (in mm) was not changed post PCI in 12 leads (1.4 +/- 0.2 vs 1.5 +/- 0.2, P = NS) while it was decreased in V(3)R through V(5)R (0.2 +/- 0.2 vs 1.2 +/- 0.3, P < .01).

CONCLUSIONS

The addition of V(3)R through V(5)R improves the diagnostic ability of standard exercise testing in detecting silent ischemia due to restenosis in patients undergoing PCI in RCA or/and LCX.