Angiographically visible coronary artery collateral circulation improves prognosis in patients presenting with acute ST segment-elevation myocardial infarction.

BACKGROUND: Coronary collaterals are often seen supplying retrograde flow to an acutely occluded arterial territory. Whether this early collateralization offers prognostic benefit is not well established. METHODS: We analyzed data from all patients presenting to our regional cardiac unit with acute ST-elevation myocardial infarction requiring immediate angiography (years 1999-2017). Data on all patients is entered prospectively into a bespoke tailored database prior to knowledge of patient outcome. Only patients with TIMI 0 or 1 flow in the infarct-related vessel were included in the analysis. In-hospital and long-term outcome were assessed according to the presence or absence of angiographically visible collateral flow prior to treatment of the occluded vessel. RESULTS: Two thousand five hundred and forty-two patients were included in the analysis. 76% of these (n = 1944) had TIMI 0/1 flow at angiography. Angiographically-visible collateralization was seen in 17% (n = 322) and was more commonly observed in the right coronary artery (64%) than in the left anterior descending (25%) or Cx (6%). Cardiogenic shock (10.8%) and use of an intra-aortic balloon pump (5.4%) were more frequent in patients without coronary collateralisation (p = .04 and p = .02, respectively). The presence of collaterals improved long term survival (95% CI 11.4-18.7 months; p < .01). CONCLUSION: One-sixth of patients with STEMI have angiographically visible collaterals to the infarcted territory. Patients without collaterals are more likely to present in cardiogenic shock. The presence of angiographically visible collaterals at the time of STEMI is associated with an improved long-term survival.

Acute ischemic complications of PCI and CABG: who should cover whom for coronary revascularization?

INTRODUCTION: Percutaneous coronary intervention (PCI) has historically required cardiothoracic backup in the event of ischemic complications. However, many complications occurring during PCI can now be effectively treated at the time of the indexed procedure. Equally, ischemic complications, which occur following coronary artery bypass grafting (CABG), which were previously treated medically or with reoperation, may now also be effectively treated by acute PCI. AIMS AND METHODS: To identify the rate, cause, treatment, and outcomes of ischemic complications from PCI or isolated CABG procedures undertaken from January 2004 to January 2011 where there was immediate crossover from PCI to CABG or vice versa, and to determine from the indexed revascularization procedure, whether or not the ischemic complications were rectified by either CABG with respect to PCI or PCI with respect to CABG. RESULTS: Three hundred fifty-six PCI major ischemic complications were identified. Three hundred forty-seven (97.5%) were rectified percutaneously and 9 (2.5%) required emergency CABG. The commonest reason for emergency CABG was occlusive dissection (n=7). Of the 9 patients that underwent emergency CABG, 3 patients (33.3%) died. Forty CABG major ischemic complications were identified. Twenty-seven (67.5%) were treated medically. Thirteen (32.5%) underwent diagnostic angiography. The etiology of the ischemia was found in all cases. Consequently, 2 underwent reoperation, one was treated medically, and 10 underwent acute PCI. CONCLUSION: Acute coronary ischemia remains a small but significant complication of both PCI and CABG. Resolution of ischemia requires prompt diagnosis and early discussion between cardiothoracic surgeon and cardiac interventionalist to determine the safest and therefore most appropriate way to resolve the problem.

Randomized trials of clinical networks in the management of ST-elevation MI: can they be performed?

PURPOSE OF THIS REVIEW: Mortality in ST segment elevation myocardial infarction is directly related to the degree of myocardial damage sustained as a result of vessel occlusion. It is well established that the temporal window during which myocardial salvage may be achieved is limited. RECENT FINDINGS: Prehospital thrombolysis, facilitated percutaneous coronary intervention (PCI) and prompt transfer to institutions with primary PCI capabilities have all been proposed as strategies to augment the temporal window. These different approaches all seek to modify the way reperfusion is delivered, as opposed to the manner of restoring flow, but have been associated with mixed results. Hence, it has become clear that further mortality reductions will require system-based and highly coordinated clinical networks. SUMMARY: The extent of the mortality benefit associated with the development of an integrated reperfusion network has yet to be established. Collection of robust data in the context of a clinical trial may be obtained by the random allocation of clinical networks as opposed to randomization of patients. Furthermore, such data would be applicable to 'real world' clinical practice, as optimal reperfusion could be examined in patients whose complex comorbidity would preclude their inclusion in conventional ST segment elevation myocardial infarction (STEMI) trials.

Clinical outcomes with 6 months dual antiplatelet therapy after implantation of biolimus-A9 drug eluting coronary stents.

INTRODUCTION: Duration of dual antiplatelet therapy (DAPT) following drug eluting stent (DES) implantation remains poorly defined. Endothelialisation of biodegradable polymer biolimus-eluting stents occurs early, and 6 months DAPT may be adequate. AIMS: We evaluated long term outcome in patients treated with biolimus-eluting stents who were treated with 6 months DAPT. Endpoints included cardiac death and non-fatal stent thrombosis occurring 6 to 12 months after stent implantation. METHODS: 692 patients (77.2% male), aged 65.6 ± 12.5 years received biolimus-eluting DES (March 2008 -November 2011). Vital status was tracked through the Medical Research Information Service. Episodes of non-fatal stent thrombosis, (Academic Research Consortium definition) between months 6 and 12 were tracked via systematic database searches (5 PCI centres). RESULTS: Presentations included acute coronary syndrome (47.2%) and stable coronary disease (52.8%). Vessels treated included left main stem (6.8%), left anterior descending (37.4%), circumflex (19.1%), right coronary artery (34.5%) and saphenous vein graft (2.1%) respectively. High-risk subsets included diabetes (15.6%); AHA type C lesions (35.1%) and chronic total occlusions (12.8%). During median follow-up of 700 days (0 to 1392) there were 42 deaths (6.1%); 4.2% at 0-6 months, 1.0% at 6-12 months and 0.9% at >12 months. Of the 7 deaths between 6 and 12 months, one death was adjudicated as possible stent thrombosis. There were no cases of non-fatal known stent thrombosis. All cause mortality accrued with smooth decremental incidence. Statistical examination showed no evidence of event clustering between 6 and 12 months. CONCLUSIONS: After implantation of biodegradable polymer biolimus-eluting coronary stents, 6 months DAPT appears to be adequate, safe and effective.

Prospective peer review of regional percutaneous interventional procedures: a tool for quality control and revalidation.

AIMS: Current quality measures of percutaneous coronary intervention (PCI) procedures are based on the incidence of major adverse cardiac events (MACE). This crude marker ignores the many clinical nuances that make for sound decision making in PCI. We have established a prospective peer review audit tool to determine the quality of PCI within our cardiac network, which consists of five PCI hospitals serving a population of 1.4 million people in Sussex, UK. METHODS AND RESULTS: Analysis of 10% of all PCI cases selected at random each month by a non-clinical audit manager is made by a rotating panel of two PCI operators and one cardiac surgeon. Each PCI case is assessed for anatomical suitability, lesion severity, strategic appropriateness and final outcome. Panel findings were reported back to the operator and the audit manager. A total of 326 cases were assessed by the review committee. Results were disseminated to individual operators. Coronary anatomy and lesion severity were considered appropriate for PCI in 94.2% and 96.0% of cases, respectively. Appropriateness of strategy was confirmed in 86.2% and the outcome considered satisfactory in 90.8%. A total of 242 subsequent cases were analysed to assess practice trends. This analysis demonstrated a statistically significant improvement in clinical decision making with respect to appropriateness of strategy (from 86.2% to 92.6%; p=0.004). CONCLUSIONS: Prospective peer review of percutaneous coronary intervention cases by a rotating regional committee is valuable in ensuring procedural quality.

The pressure wire in practice.

Fractional flow reserve (FFR) is increasingly used to evaluate the functional significance of epicardial coronary disease. When compared with non-invasive techniques this index has superior sensitivity and specificity, is largely independent of prevailing haemodynamic conditions and has an unequivocal normal value. Furthermore, it can be used at the time of invasive coronary assessment. FFR measurements are invaluable for evaluation of intermediate coronary lesions but clinical decisions must be based on accurate measurements and an understanding of the limitations of the data supporting its use. This article identifies procedural and clinical issues pertaining to measurement of FFR and identifies potential pitfalls and situations where interpretation can be difficult; for example, the presence of serial stenoses and left main stem disease, its use in specific conditions such as diffuse epicardial disease, microvascular abnormalities, left ventricular dysfunction and acute coronary syndromes.