Italo Porto

Troponin elevation after percutaneous coronary intervention directly represents the extent of irreversible myocardial injury: insights from cardiovascular magnetic resonance imaging

Background—Although troponin elevation after percutaneous coronary intervention (PCI) is common, uncertainties remain about the mechanisms of its release and its relationship to the volume of myocardial tissue loss. Delayed-enhancement MRI of the heart has been shown to reliably quantify areas of irreversible myocardial injury. To investigate the quantitative relationship between irreversible injury and cardiac troponin release, we studied the incidence and extent of new irreversible injury in patients undergoing PCI and correlated it to postprocedural changes in cardiac troponin I. Methods and Results—Fifty patients undergoing PCI were studied with preprocedural and postprocedural (24 hours) delayed-enhancement MRI for assessment of new irreversible myocardial injury. Cardiac troponin I measurements were obtained before PCI and 24 hours after PCI. Of these 50 patients, 24 underwent a further third MRI scan at a median of 8 months after the procedure. Mean patient age was 64±12 years. After the procedure, 14 patients (28%) had evidence of new myocardial hyperenhancement, with a mean mass of 6.0±5.8 g, or 5.0±4.8% of total left ventricular mass. All of these patients had raised troponin I levels (range 1.0 to 9.4 &mgr;g/L). Thirty-four patients (68%) had no elevated troponin I and no evidence of new myocardial necrosis on MRI. There was a strong correlation between the rise in troponin I measurements at 24 hours and mean mass of new myocardial hyperenhancement, both early (r=0.84; P<0.001) and late (r=0.71; P<0.001) after PCI, although there was a trend for a reduction in the size of PCI-induced myocardial injury in the late follow-up scan (P=0.07). Conclusions—In the setting of PCI, patients demonstrating postprocedural elevation in troponin I have evidence of new irreversible myocardial injury on delayed-enhancement MRI. The magnitude of this injury correlates directly with the extent of troponin elevation.

Angiography alone versus angiography plus optical coherence tomography to guide decision-making during percutaneous coronary intervention: the Centro per la Lotta contro l'Infarto-Optimisation of Percutaneous Coronary Intervention (CLI-OPCI) study.

AIMS Angiographic guidance for percutaneous coronary intervention (PCI) has substantial limitations. The superior spatial resolution of optical coherence tomography (OCT) could translate into meaningful clinical benefits. We aimed to compare angiographic guidance alone versus angiographic plus OCT guidance for PCI. METHODS AND RESULTS Patients undergoing PCI with angiographic plus OCT guidance (OCT group) were compared with matched patients undergoing PCI with angiographic only guidance (Angio group) within 30 days. The primary endpoint was the one-year rate of cardiac death or myocardial infarction (MI). A total of 670 patients were included, 335 in the OCT group and 335 in the Angio group. OCT disclosed adverse features requiring further interventions in 34.7%. Unadjusted analyses showed that the OCT group had a significantly lower one-year risk of cardiac death (1.2% vs. 4.5%, p=0.010), cardiac death or MI (6.6% vs. 13.0%, p=0.006), and the composite of cardiac death, MI, or repeat revascularisation (9.6% vs. 14.8%, p=0.044). Angiographic plus OCT guidance was associated with a significantly lower risk of cardiac death or MI even at extensive multivariable analysis adjusting for baseline and procedural differences between the groups (OR=0.49 [0.25-0.96], p=0.037) and at propensity-score adjusted analyses. CONCLUSIONS This observational study, the first ever formally to appraise OCT guidance for PCI decision-making, suggests that the use of OCT can improve clinical outcomes of patients undergoing PCI.

Plaque Volume and Occurrence and Location of Periprocedural Myocardial Necrosis After Percutaneous Coronary Intervention Insights From Delayed-Enhancement Magnetic Resonance Imaging, Thrombolysis in Myocardial Infarction Myocardial Perfusion Grade Analysis, and Intravascular Ultrasound

Background— Myocardial necrosis can occur during percutaneous coronary intervention (PCI) despite optimal adjunctive pharmacology and careful technique. We investigated the mechanisms of procedural infarction using angiographic analysis, intravascular ultrasound, and delayed-enhancement magnetic resonance imaging. Methods and Results— Fifty-two patients (64 vessels) who underwent complex PCI were studied. All patients were preloaded with clopidogrel and received glycoprotein IIb/IIIa inhibitors. “Adjacent” myonecrosis was defined as the presence of an area of new gadolinium hyperenhancement close to the stent. “Distal” myonecrosis was defined as situated at least 10 mm downstream from the stent. Fifteen vessels (23%) had evidence of new hyperenhancement after PCI. Of these, 8 (12%) had the distal type, and 7 (11%) had the adjacent type. Intravascular ultrasound showed a significantly greater reduction in plaque volume (91.6±51.5 versus 8±14 versus 20±35 mm3; P<0.001) in the group with distal hyperenhancement compared with patients without new hyperenhancement or adjacent hyperenhancement. In the entire sample, a significant correlation was seen between changes in plaque volume (&rgr;=0.58, P<0.001) after PCI and the mass of new necrosis measured by magnetic resonance imaging. Thrombolysis in Myocardial Infarction perfusion grade assessment of a closed microvasculature after PCI carried an odds ratio of 8.0 (95% confidence interval, 1.4 to 46.1; P=0.02) for the occurrence of hyperenhancement, whereas side-branch occlusion was associated with an odds ratio of 16.2 (95% confidence interval, 2.6 to 102.5; P=0.03). However, a closed microvasculature was associated with distal hyperenhancement (P=0.02), and side-branch occlusion was associated with adjacent hyperenhancement (P<0.001). Conclusions— These data suggest that distal embolization of plaque material occurs in contemporary PCI of native coronary arteries. Efforts to minimize procedural necrosis may require careful review of side branch anatomy and/or use of distal protection during extensive coronary stenting.

Drug-Eluting Balloon in Peripheral Intervention for Below the Knee Angioplasty Evaluation (DEBATE-BTK) A Randomized Trial in Diabetic Patients With Critical Limb Ischemia

Background— The 1-year restenosis rate after balloon angioplasty of long lesions in below-the-knee arteries may be as high as 70%. Our aim was to investigate the efficacy of a paclitaxel drug-eluting balloons versus conventional percutaneous transluminal angioplasty (PTA) for the reduction of restenosis in diabetic patients with critical limb ischemia undergoing endovascular intervention of below-the-knee arteries. Methods and Results— The Drug-Eluting Balloon in Peripheral Intervention for Below the Knee Angioplasty Evaluation (DEBATE-BTK) is a randomized, open-label, single-center study comparing drug-eluting balloons and PTA. Inclusion criteria were diabetes mellitus, critical limb ischemia (Rutherford class 4 or higher), significant stenosis or occlusion >40 mm of at least 1 below-the-knee vessel with distal runoff, and life expectancy >1 year. Binary in-segment restenosis at a 1-year angiographic or ultrasonographic follow-up was the primary end point. Clinically driven target lesion revascularization, major amputation, and target vessel occlusion were the secondary end points. One hundred thirty-two patients with 158 infrapopliteal atherosclerotic lesions were enrolled. Mean length of the treated segments was 129±83 mm in the drug-eluting balloon group compared with 131±79 mm in the PTA group (P=0.7). Binary restenosis, assessed by angiography in >90% of patients, occurred in 20 of 74 lesions (27%) in the drug-eluting balloon group compared with 55 of 74 lesions (74%) in the PTA group (P<0.001); target lesion revascularization, in 12 (18%) versus 29 (43%; P=0.002); and target vessel occlusion, in 12 (17%) versus 41 (55%; P<0.001). Only 1 major amputation occurred, in the PTA group (P=0.9). Conclusions— Drug-eluting balloons compared with PTA strikingly reduce 1-year restenosis, target lesion revascularization, and target vessel occlusion in the treatment of below-the-knee lesions in diabetic patients with critical limb ischemia. Clinical Trial Registration— URL: http://ClinicalTrials.gov. Unique identifier: NCT01558505.Background— The 1-year restenosis rate after balloon angioplasty of long lesions in below-the-knee arteries may be as high as 70%. Our aim was to investigate the efficacy of a paclitaxel drug-eluting balloons versus conventional percutaneous transluminal angioplasty (PTA) for the reduction of restenosis in diabetic patients with critical limb ischemia undergoing endovascular intervention of below-the-knee arteries. Methods and Results— The Drug-Eluting Balloon in Peripheral Intervention for Below the Knee Angioplasty Evaluation (DEBATE-BTK) is a randomized, open-label, single-center study comparing drug-eluting balloons and PTA. Inclusion criteria were diabetes mellitus, critical limb ischemia (Rutherford class 4 or higher), significant stenosis or occlusion >40 mm of at least 1 below-the-knee vessel with distal runoff, and life expectancy >1 year. Binary in-segment restenosis at a 1-year angiographic or ultrasonographic follow-up was the primary end point. Clinically driven target lesion revascularization, major amputation, and target vessel occlusion were the secondary end points. One hundred thirty-two patients with 158 infrapopliteal atherosclerotic lesions were enrolled. Mean length of the treated segments was 129±83 mm in the drug-eluting balloon group compared with 131±79 mm in the PTA group ( P =0.7). Binary restenosis, assessed by angiography in >90% of patients, occurred in 20 of 74 lesions (27%) in the drug-eluting balloon group compared with 55 of 74 lesions (74%) in the PTA group ( P <0.001); target lesion revascularization, in 12 (18%) versus 29 (43%; P =0.002); and target vessel occlusion, in 12 (17%) versus 41 (55%; P <0.001). Only 1 major amputation occurred, in the PTA group ( P =0.9). Conclusions— Drug-eluting balloons compared with PTA strikingly reduce 1-year restenosis, target lesion revascularization, and target vessel occlusion in the treatment of below-the-knee lesions in diabetic patients with critical limb ischemia. Clinical Trial Registration— URL: . Unique identifier: [NCT01558505][1]. # Clinical Perspective {#article-title-23} [1]: /lookup/external-ref?link_type=CLINTRIALGOV&access_num=NCT01558505&atom=%2Fcirculationaha%2F128%2F6%2F615.atom

Inflammatory gene polymorphisms and ischaemic heart disease: review of population association studies

Inflammation and genetics are both prominent mechanisms in the pathogenesis of atherosclerosis and arterial thrombosis. Accordingly, a number of population studies have explored the association of ischaemic heart disease with gene polymorphisms of the inflammatory molecules tumour necrosis factors (TNF) α and β, transforming growth factors (TGF) β1 and 2, interleukin (IL) 1 and its receptor antagonist (IL 1ra), CD14 (the receptor for lipopolysaccharide), P and E selectins, and platelet endothelial cell adhesion molecule (PECAM) 1. Although they are very preliminary and partly conflicting, the data provide some evidence that alterations in the genetics of the inflammatory system may modify the risk of ischaemic heart disease.

Resting Myocardial Blood Flow Is Impaired in Hibernating Myocardium. A Magnetic Resonance Study of Quantitative Perfusion Assessment

Background— Although impairment in perfusion reserve is well recognized in hibernating myocardium, there is substantial controversy as to whether resting myocardial blood flow (MBF) is reduced in such circumstances. Quantitative first-pass cardiovascular magnetic resonance (CMR) perfusion imaging allows absolute quantification of MBF. We hypothesized that MBF assessed at rest by quantitative CMR perfusion imaging is reduced in hibernating myocardium. Methods and Results— Twenty-seven patients with 1 or 2-vessel coronary disease and at least 1 dysfunctional myocardial segment undergoing PCI were studied with preprocedure, early (24 hours), and late (9 months) postprocedure CMR imaging. First-pass perfusion images at rest were acquired in 3 short-axis planes by use of a T1-weighted turboFLASH sequence. In each slice, MBF was determined for 8 myocardial segments in mL · min−1 · g−1 by deconvolution of signal intensity curves with an arterial input function measured in the left ventricular blood pool. Cine MRI for assessment of global and segmental function and delayed enhancement MRI for detection of viability were also obtained. All coronary lesions were 80% to 95% stenosis in severity. Over all segments, mean MBF normalized by rate-pressure product (“corrected MBF”) was 1.2±0.3 mL · min−1 · g−1 · (mm Hg · bpm/104)−1 in segments without significant coronary stenosis and 0.7±0.2 mL · min−1 · g−1 · (mm Hg · bpm/104)−1 in segments with coronary stenosis before PCI (mixed model controlling for slice and segment z=−23.9, P<0.001). Early after the procedure, the MBF was 1.2±0.2 mL · min−1 · g−1 · (mm Hg · bpm/104)−1 in revascularized segments and 1.3±0.2 mL · min−1 · g−1 · (mm Hg · bpm/104)−1 in nondiseased segments (z=−6.1, P<0.001). Late after PCI, the systolic wall thickening and end-diastolic wall thickness both increased significantly more (both P<0.001) in the myocardial segments subtended by severe coronary stenosis (8±17% to 40±19% and 6.5±1.1 to 9.3±2 mm, respectively) than in the myocardial segments supplied by nondiseased vessels. Mean MBF in dysfunctional segments with significantly improved contraction after revascularization was 0.8±0.2 mL · min−1 · g−1 · (mm Hg · bpm/104)−1 before PCI and 1.2±0.2 mL · min−1 · g−1 · (mm Hg · bpm/104)−1 after PCI (z=2.0, P=0.04). Conclusions— CMR perfusion imaging detects impaired resting MBF in hibernating myocardial segments.

Myocardial infarction after percutaneous coronary intervention: a meta-analysis of troponin elevation applying the new universal definition

AIM Elevation of Troponin after scheduled percutaneous coronary intervention (PCI) is a recognized consequence. We sought to evaluate the prognostic significance and impact of the newly published definition of PCI-related myocardial infarction (MI) according to which any troponin elevation >3 times the upper reference limit identify a peri-procedural MI. METHODS Search of BioMedCentral, CENTRAL, mRCT and PubMed (updated May 2008). Outcomes of interest were: MACE [the composite of all cause death, MI, repeat target vessel PCI (re-PCI) and coronary artery bypass grafting (CABG)]; single end points were also assessed. RESULTS Fifteen studies have been included totalling 7578 patients. Troponin elevation occurred in 28.7% of the procedures. The incidence of PCI-related MI according to the new definition was 14.5%. During the hospitalization, any level of raised troponin was associated with an increased risk of MACE [OR 11.29 (3.00-42.48), Number needed to harm (NNH) 5], death [OR 7.16 (1.95-26.27), NNH = 100], MI [OR 30.85 (6.05-157.38), NNH = 4] and re-PCI [OR 4.13 (1.23-13.88), NNH = 50]. Patients with PCI-related MI had an increased risk of death [OR 17.25 (2.71-109.96), NNH = 100] and re-PCI [OR 10.86 (3.2-36.94), NNH = 25]. At follow up of 18 months any troponin elevation was associated with an increased risk of MACE [OR 1.48 (1.12-1.96), NNH = 20], death [OR 2.19 (1.59-3.00), NNH = 50], MI [OR 3.29 (2.71-6.31), NNH = 33] and re-PCI [OR 1.47 (1.06-2.03), NNH = 25]. In patients with PCI-related MI the risk of MACE was further increased: OR 2.25 (1.26-4.00), NNH = 3. An increase of the troponin level below the cut-off was not associated with MACE. CONCLUSION A diagnosis of MI according to the new guidelines applies to 15% of patients undergoing PCI and these patients are at high risk of further adverse events both during the hospital stay and at 18 months.

The Syntax score predicts peri-procedural myocardial necrosis during percutaneous coronary intervention.

BACKGROUND Peri-procedural myocardial injury (PPI) during percutaneous coronary intervention (PCI) is common and associated with a poor outcome. No reliable angiographic or clinical predictors of PPI exist. We evaluated the ability of the SYNTAX score (SXscore), Gensini score, American Heart Association/American College of Cardiology (AHA/ACC) and Society for Cardiovascular Angiography and Intervention (SCAI) classifications to predict PPI. METHODS Consecutive patients were included from two existing databases of PCI. Patients with coronary bypass grafts or instent restenosis were excluded. PPI was defined as troponin I elevation (>1.0 microg/L) at 6-24 h post-PCI. Delayed enhancement magnetic resonance imaging distinguished PPI territory in patients undergoing multi-vessel PCI. Quantitative coronary angiography was performed blinded to PPI. In total, 100 patients underwent PCI to 122 vessels. PPI occurred in 20/100 (20.0%) patients. RESULTS Mean patient SXscore was higher in patients with PPI (20.6 vs. 12.4, p = 0.0001), however Gensini score was not significantly different (34.2 vs. 27.3, p = 0.15). Mean vessel SXscore was higher in vessels associated with PPI (12.1 vs. 7.6, p = 0.002), but not different for vessel Gensini score (16.2 vs. 13.6, p = 0.42). No vessels with AHA type A or B1 lesions were associated with PPI. Higher AHA scores (B2 and C) were associated with PPI (chi2 for trend 11.6, p = 0.0007). SCAI scores were not predictive of PPI (chi2 for trend 3.6, p = 0.06). By ROC analysis, a patient SXscore of > or = 17 predicted PPI with a sensitivity of 75.0% and specificity of 70.0%. CONCLUSION Higher SXscores are predictive of myocardial injury, whilst AHA type A and B1 lesions have a high negative predictive value for PPI.

EuroSCORE as predictor of in-hospital mortality after percutaneous coronary intervention

Objective: To date, no common risk stratification system is available to predict the risk of surgical or percutaneous myocardial revascularisation in patients with coronary artery disease (CAD). Thus, we sought to assess the European System for Cardiac Operative Risk Evaluation (EuroSCORE) validity to predict in-hospital mortality after percutaneous coronary intervention (PCI). Design, setting and participants: EuroSCORE was prospectively and systematically assessed in 1173 consecutive patients undergoing PCI in a high-volume single centre between April 2005 and October 2006. Main outcome measure: The receiver-operating characteristics (ROC) curve was used to describe performance and accuracy of the EuroSCORE risk model for the prediction of in-hospital mortality after PCI. Results: The EuroSCORE model demonstrated an overall relation between EuroSCORE rank and the incidence of in-hospital mortality, showing consistency in predicting patient risk across many subgroups and levels of global risk. At multivariable logistic regression analysis the EuroSCORE value was an independent in-hospital mortality predictor (p = 0.002) together with left main disease (p = 0.005), procedural urgency (p = 0.001), ACC/AHA C type lesion (p = 0.02) and PCI failure (p = 0.01). The area under the ROC curve for the EuroSCORE system was 0.91 (95% CI 0.86 to 0.97), indicating a good ability of the model to discriminate patients at risk of dying during the index hospitalisation. Conclusion: The EuroSCORE risk model, already extensively validated for the prediction of early mortality following open-heart surgery, can also be efficiently utilised in the setting of PCI. The introduction of the EuroSCORE assessment in patients with documented CAD may help to improve the revascularisation strategy decision-making process.

Temporal evolution and functional outcome of no reflow: sustained and spontaneously reversible patterns following successful coronary recanalisation.

Objective: To identify in humans the temporal patterns of no reflow and their functional implications. Methods: 24 patients with first acute myocardial infarction and successful coronary recanalisation by recombinant tissue-type plasminogen activator (n = 15) or primary percutaneous transluminal coronary angioplasty (n = 9) were studied by myocardial contrast echocardiography within 24 hours of recanalisation and at one month’s follow up. Myocardial contrast echocardiography was performed by intermittent harmonic power Doppler and intravenous Levovist. The regional contrast score index (CSI) was calculated within dysfunctioning myocardium. Videointensity was measured (dB) within risk and control areas and their ratio was calculated. Results: In 8 patients reflow was observed at 24 hours and persisted at one month. Conversely in 16 patients areas of no reflow were detectable at 24 hours. At one month, no reflow was spontaneously reversible in 9 patients (mean (SD) CSI and videointensity ratio improved from 2.5 (0.5) to 1.4 (0.6) and from 0.6 (0.1) to 0.7 (0.1), respectively; p < 0.05) and was sustained in the remaining 7 patients (CSI and videointensity ratio remained unchanged from 2.6 (0.6) to 2.6 (0.5) and from 0.5 (0.2) to 0.5 (0.2), respectively; NS). Left ventricular function improved significantly in patients with reflow and reversible no reflow. Volumes were enlarged only in patients with sustained no reflow. Conclusions: No reflow detected at 24 hours may be sustained or spontaneously reversible at one month. Such reversibility of the phenomenon is associated with preserved left ventricular volumes and function. Clarification of the mechanisms of delayed reversibility may lead to tailored treatment of no reflow even in the subacute phase of myocardial infarction.