Exercise stress testing before and after successful multivessel percutaneous transluminal coronary angioplasty

The Predictive Value of ΣΔST/ΔHR Index for Restenosis after Percutaneous Coronary Intervention

Objective

To find out the predictive value of the ΣΔST/ΔHR index for restenosis after percutaneous coronary intervention (PCI).

Method

Subjects of this research were patients who participated in a cardiac rehabilitation (CR) program as six to eight weeks of a hospital-based program after receiving PCI to treat acute coronary syndrome (ACS). The patients received coronary angiography (CAG) at the onset of the ACS and nine months after that, and also received an exercise tolerance test (ETT) at the start of the CR program and several days before receiving a follow-up CAG. In ETT, we used the sum of the ST depression (ΣΔST index) of leads II, III, aVF, V_4-6 as well as the sum of the ΔST/ΔHR (heart rate) (ΣΔST/ΔHR index) in the same leads and the sum of the ΔST/ΔRPP (rate pressure product) (ΣΔST/ΔRPP index) in the same leads. We compared the predictive power of each index of ETT for restenosis after PCI.

Results

The sensitivity, specificity, positive predictive value, and negative predictive value of ΣΔST index were 69%, 47%, 31%, and 82%. The ΣΔST/ΔHR index was 13.7±5.2 in the restenosis group and 9.3±5.6 in the patent group (p=0.017). The sensitivity, specificity, positive predictive value, and negative predictive value of this index were 85%, 63%, 44%, and 92%. The ΣΔST/ΔRPP index were 0.10±0.08 in the restenosis group and 0.06±0.04 in the patent group (p=0.016). The sensitivity, specificity, positive predictive value, and negative predictive value of this index were 54%, 76%, 44%, and 83%.

Conclusion

The ΣΔST/ΔHR index showed a much higher sensitivity and negative predictive value for restenosis after PCI compared to the ΣΔST index.

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.