Intracoronary ST-segment shift soon after elective percutaneous coronary intervention accurately predicts periprocedural myocardial injury.

BACKGROUND: Elevation of cardiac biomarkers after coronary angioplasty (percutaneous coronary intervention [PCI]) reflects periprocedural myocardial damage and is associated with adverse cardiac events. We assessed whether periprocedural myocardial damage that occurs despite successful PCI could be rapidly and easily identified by intracoronary ST-segment recording with the use of a catheter guidewire. METHODS AND RESULTS: In 108 consecutive stable patients undergoing elective single-vessel PCI, we recorded unipolar ECG from the intracoronary guidewire in the distal coronary before PCI and 2 minutes after the last balloon inflation. After PCI, intracoronary ST-segment shift > or = 1 mm from baseline was considered significant. Troponin I levels were measured at baseline and at 8 and 24 hours after intervention, and myocardial damage was defined as troponin I increase above the upper normal value after intervention. All patients had normal cardiac marker values before PCI, and PCI was successful in all (residual stenosis < 20%, Thrombolysis in Myocardial Infarction grade 3 flow). After PCI, long-term follow-up data were collected; myocardial damage was detected in 50 patients (46%), although abnormal creatine kinase-MB values were documented in only 11 (10%). Significant intracoronary ST-segment shift after PCI was present in 40 patients (37%; group A) and absent in the remaining 68 (63%; group B). Procedural myocardial damage was documented in 37 group A patients (93%) and in 13 group B patients (19%; P<0.001); significant ECG changes were found on standard ECG after intervention in only 5 patients (13%) and 1 patient (1%) (P<0.05). Sensitivity of intracoronary ST-segment shift for predicting myocardial damage was 74%, and specificity was 95%, with positive and negative predictive values of 93% and 81%, respectively. On multivariate analysis, intracoronary ST-segment shift was the sole independent predictor of myocardial damage (odds ratio, 54.1; 95% confidence interval, 12.1 to 240; P<0.0001). At a median follow-up of 12+/-5 months, major coronary event-free survival was significantly worse in group A patients (log-rank test chi2=4.0; P<0.05). CONCLUSIONS: After successful single-vessel PCI, intracoronary ST-segment shift allows the prompt and inexpensive identification of patients developing myocardial injury, who may require adjunctive therapy and longer in-hospital stay.

Intracoronary electrocardiogram ST segment shift evaluation during intravenous adenosine infusion: a comparison with fractional flow reserve.

BACKGROUND: By measuring the pressure decline caused by coronary narrowing, fractional flow reserve (FFR) is an index of the physiological significance of a vessel stenosis. Intracoronary electrocardiogram (IC-ECG) recording from an angioplasty guidewire is more sensitive than standard ECG in detecting regional myocardial ischemia. The aim of the study was to assess if unipolar IC-ECG ST segment recording from angioplasty guidewire during maximal pharmacologic vasodilation could be used as an indirect estimation of FFR results. METHODS: Forty-eight clinically stable patients with intermediate stenosis underwent FFR evaluation and IC-ECG recording during intravenous adenosine infusion. RESULTS: FFR values were ≤ 0.80 in 26 (54%) patients and > 0.80 in 22 (46%). After adenosine, standard ECG was abnormal in only nine (19%) patients, while IC-ECG showed a significant ST segment shift (IST) in 24 (50%) patients: ST elevation in 19 patients and depression in five). IST was documented in 21/26 patients with FFR ≤ 0.80 (81%) and in 3/22 with FFR > 0.80 (p < 0.001). Sensitivity of IST for predicting an abnormal FFR value was 81%, specificity 86%, positive and negative predictive accuracies were 88% and 79%, respectively. CONCLUSIONS: Intracoronary ST segment shift evaluation during adenosine infusion may be of value in assessing the functional significance of a borderline stenosis. The presence of IST during adenosine infusion could obviate the need for additional FFR evaluation.

Operator volume and outcomes of primary angioplasty for acute myocardial infarction in a single high-volume centre.

OBJECTIVE: The guidelines for the management of ST-elevation myocardial infarction (STEMI) state the minimum operator volume for percutaneous coronary interventions (PCIs), without strong evidence of a relationship between operator volume and outcomes of primary angioplasty, at variance with elective practice. We sought to investigate the effect of operator volume on primary PCI for STEMI. METHODS: Three hundred and thirty-one consecutive STEMI patients were treated over 19 months with primary PCI in a high-volume centre without on-site cardiac surgery. Three skilled operators, with very different volumes of interventional practice, performed the PCI procedures around-the-clock. RESULTS: Operators were divided into very high (A), intermediate high (B) and low high volume (C). Demographic, clinical, angiographic, and procedural characteristics of the patient population did not differ among operators, with the exception of three-vessel disease (P = 0.016), circumflex infarct-related artery (P = 0.002), mechanical support (P = 0.02), use of abciximab (P = 0.003) for operator C, use of tirofiban for operator B (P = 0.02), and type of stent for operator A (P = 0.0004). Similarly, no differences were observed among operators in in-hospital outcomes (death, a composite of major adverse cardiovascular events, ST-segment resolution, thrombolysis in myocardial infarction flow grade 3, length of hospitalization) and haemorrhagic complications. CONCLUSIONS: Our data show that there is not a significant relationship between operator volume over the threshold indicated by the guidelines, and both primary PCI early outcomes and complications in STEMI, and suggest that expertise and experience of the whole professional team rather than just of the individual operator play a major role.