Citations

September 2007 marked the 30-year anniversary of the first human percutaneous coronary intervention, an index event that changed the course of modern-day cardiovascular care. Before that first procedure, adult invasive cardiology focused on diagnostic angiography as well as hemodynamic assessment of structural heart disease. Since that initial procedure, percutaneous coronary intervention has become the most frequently performed coronary revascularization procedure worldwide. Several factors have been responsible for this dramatic paradigm shift, the most prominent being identification of opportunities for technical improvement and the application of innovation and investigation in concert with colleagues, professional societies, and industry. These approaches will continue to be of paramount importance as new technologies are brought to bear on an increasingly broader group of patients with cardiovascular disease.

Background— Myonecrosis after percutaneous coronary intervention (PCI) has been correlated with a worse prognosis, but controversy exists about the clinical significance and potential mechanisms for the association. The aim of this study was to evaluate the relative impact of preprocedural and postprocedural cardiac troponin T (cTnT) levels on survival rate after PCI. Methods and Results— We evaluated 5487 patients from the Mayo Clinic registry who required nonemergency PCI, and we examined the relationship between periprocedural cTnT levels, with the 99th percentile cutoff value used for normal (<0.01 ng/mL), and outcomes. The patients were divided into 3 groups: normal preprocedural and postprocedural cTnT levels (no myonecrosis), normal preprocedural but elevated postprocedural cTnT levels (PCI-related myonecrosis), and abnormal preprocedural cTnT. The 30-day death rates were 0.1%, 0.6%, and 2.3%, respectively, in the 3 groups. In a multivariable model, an abnormal pre-PCI cTnT level (hazard ratio 9.66 [2.30–40.57]; P =0.002), and PCI-related myonecrosis (4.71 [1.02–21.83]; P =0.048) were independent predictors of 30-day mortality. Over a median follow-up of 28 months, an abnormal pre-PCI cTnT level (hazard ratio 1.79 [1.35–2.39]; P <0.001) independently predicted death, but the occurrence of PCI-related myonecrosis did not. A postprocedural elevation in creatine kinase MB fraction was not an independent predictor of long-term risk of death (0.912 [0.70–1.19]; P =0.5). Conclusions— A preprocedural cTnT level >0.01 is a powerful independent predictor of prognosis after PCI and is of greater prognostic significance than the postprocedural biomarker levels. PCI-related myonecrosis occurs frequently and predicts short-term but not long-term risk of death.

Endothelin plays an important role in the pathogenesis of atherosclerosis. The aim of the study was to evaluate the safety and hemodynamic and metabolic responses to 6 months treatment with atrasentan, the selective endothelin-A receptor antagonist. Seventy-two patients with multiple cardiovascular risk factors and nonobstructive coronary artery disease on coronary angiogram were randomly assigned in a double-blind manner to atrasentan or placebo. Mean aortic blood pressure decreased from 92±10 to 80±10 mm Hg ( P <0.001) in the atrasentan group and did not change in the placebo group (93±10 and 92±11 mm Hg; P =0.84). The difference between the groups was significant ( P <0.001). No effect on heart rate was observed. In a subgroup of patients not treated with angiotensin-converting enzyme inhibitor, creatinine level decreased in the atrasentan versus the placebo group ( P =0.011). Fasting glucose ( P =0.026), glycosylated hemoglobin level ( P =0.041), triglyceride l ( P =0.013), lipoprotein-A ( P =0.046), and uric acid levels ( P =0.048) decreased significantly in the atrasentan group compared with the placebo group. No progression of angiographic coronary disease was observed. The most common adverse effects with atrasentan were nasal stuffiness, headache, and edema. In conclusion, 6 months of treatment with atrasentan results in a reduction of blood pressure and improvement in glucose and lipid metabolism. These findings suggest the beneficial role of atrasentan in the treatment of hypertension and metabolic syndrome.

There is interest in the role of growth factors in the genesis of arterial remodeling. We studied local administration of basic fibroblast growth factor (bFGF) to coronary lesions to determine whether there is a difference in remodeling and whether neovascularization could be induced in such stenoses and distal myocardium. Pigs were randomized to balloon infusion of either saline or bFGF at each thermally injured arterial site. After the animals were killed, their internal elastic lamina, neointima, and lumen areas were measured. Capillaries were counted in the arteries and myocardium. There was a greater loss of lumen and internal elastic lamina in the bFGF group. The neointima, media, and myocardium in the bFGF treated arteries had statistically more capillaries. This study showed that local intracoronary bFGF, at a dose that results in arterial luminal revascu larization in injured segments, adversely affects arterial remodeling. Thus, the angio genic response to exogenous bFGF may be offset by concomitant shrinkage of injured arterial segments.

Background— The clinical efficacy of alcohol septal ablation for drug-refractory hypertrophic cardiomyopathy remains unclear. This study examines the outcome of alcohol septal ablation performed at a tertiary hypertrophic cardiomyopathy referral center. Methods and Results— Among 601 patients with severely symptomatic obstructive hypertrophic cardiomyopathy referred for alcohol septal ablation or myectomy from 1998 to 2006, 138 patients (median age, 64 years; 39% men) chose to undergo ablation. Procedural complications included death in 1.4%, sustained ventricular arrhythmias in 3%, tamponade in 3%, and pacemaker implantation in 20%. This rate was higher than a combined complication rate of 5% in age- and gender-matched patients who had undergone septal myectomy at Mayo Clinic ( P <0.0001). Four-year survival free of all mortality was 88.0% (95% confidence interval, 79.4 to 97.5%), which was similar to that of the age- and gender-matched patients who had undergone myectomy ( P =0.18). Six patients had documented ventricular arrhythmias after ablation, 4 of whom had successful intervention. Four-year survival free of death and severe New York Heart Association class III/IV symptoms after septal ablation was 76.4%, and 71 patients (51%) became asymptomatic. Myectomy patients ≤65 years of age had significantly better survival free of death and severe symptoms ( P =0.01). Conclusions— Alcohol septal ablation is an efficacious procedure if performed in an experienced institution and may resolve symptoms in a subset of patients with obstructive hypertrophic cardiomyopathy. However, the procedural complication rate exceeds that of myectomy. Patients ≤65 years of age have better symptom resolution with myectomy. No impairment in short-term survival was noted in this nonrandomized study, but the long-term outcome remains unknown.

Background— Few studies have compared medium-term outcomes for drug-eluting stents (DES) and bare metal stents, and most are relatively small randomized controlled trials. Furthermore, since the introduction of DES, there has been increased use and duration of use of clopidogrel, statins, and other evidence-based therapies. The purpose of the present study was to compare outcomes for patients who underwent stenting in the eras before and after the introduction of DES. Methods and Results— New York state patients undergoing stenting in all nonfederal hospitals in the state were studied. Patients were excluded if they had a previous revascularization. Risk factors that were significant predictors of adverse outcomes were used to adjust adverse outcome rates. The study included 11 436 patients who received stents between October 1, 2002, and March 31, 2003, and 12 926 patients who underwent stenting between October 1, 2003, and March 31, 2004. Death rates, the combined end point of death and myocardial infarction (MI), nonfatal MI requiring readmission, target vessel revascularization, and target lesion revascularization were compared at 2 years. Patients in the DES era had significantly better risk-adjusted outcomes for death/MI (adjusted hazard ratio, 0.90; 95% confidence interval, 0.83 to 0.97), 9.9% versus 10.8%; nonfatal MI requiring readmission (adjusted hazard ratio, 0.86; 95% confidence interval, 0.76 to 0.97); target vessel revascularization (adjusted hazard ratio, 0.60; 95% confidence interval, 0.56 to 0.64), 11.2% versus 17.9%; and target lesion revascularization (hazard ratio, 0.55; 95% confidence interval, 0.51 to 0.59), 8.4% versus 14.7%. Conclusions— Patients in the DES era experienced lower rates of death/MI, nonfatal MI, target vessel revascularization, and target lesion revascularization, but there were no differences in the rates of death. These improvements are likely a result of increased use of clopidogrel, statins, and dual antiplatelet therapy, in addition to the introduction of DES.

Background— Concern regarding risk of late thrombosis after “off-label” treatment with drug-eluting stents has prompted increased use of bare-metal stents (BMS) in current practice. The sequelae of late BMS failures, however, have been poorly characterized. Methods and Results— We performed a retrospective study of 4503 consecutive patients treated with at least 1 BMS and dual antiplatelet therapy between 1994 and 2000. The cumulative incidence of stent thrombosis was 0.5% at 30 days (95% CI, 0.3% to 0.7%), 0.8% at 1 year (95% CI, 0.6% to 1.1%), and 2.0% at 10 years (95% CI, 1.5% to 2.5%). Risk of late (30 days to 1 year) and very late (>1 year) BMS thrombosis was increased among patients considered off label for drug-eluting stent use ( P =0.024). When saphenous vein graft interventions were excluded, however, risk after off-label use was not significantly increased ( P =0.23). Other correlates included vein graft intervention, prior myocardial infarction (MI), peripheral vascular disease, and ulcerated lesion ( P <0.001). Mortality was markedly increased after late and very late BMS thrombosis, particularly during the first 30 days (hazard ratios, 22 [95% CI, 3.1 to 159] and 40 [95% CI, 15 to 107], respectively). The 10-year incidence of clinical restenosis was 18.1% (95% CI, 16.5% to 19.7%), presenting with MI in 2.1% (95% CI, 1.6% to 2.6%). Restenosis presenting with MI was associated with increased mortality compared with no restenosis (hazard ratio, 2.37; P <0.001) and with restenosis with a non-MI presentation (hazard ratio, 2.42; P <0.001). Conclusions— The incidence of BMS thrombosis and of MI caused by restenosis during extended follow-up is significant. Both complications are associated with mortality.

Background Percutaneous coronary revascularization (PCI) has been increasingly applied to unprotected left main trunk (LMT) lesions, with varied long-term success. This study attempts to define the predictors of outcome in this population. Methods and Results Two hundred seventy-nine consecutive patients who had LMT PCI at 1 of 25 sites between 1993 and 1998 were studied. Forty-six percent of these patients were deemed inoperable or at high surgical risk. Thirty-eight patients (13.7%) died in hospital, and the rest were followed up for a mean of 19 months. The 1-year incidence was 24.2% for all-cause mortality, 20.2% for cardiac mortality, 9.8% for myocardial infarction, and 9.4% for CABG. Independent correlates of all-cause mortality were left ventricular ejection fraction ≤30%, mitral regurgitation grade 3 or 4, presentation with myocardial infarction and shock, creatinine ≥2.0 mg/dL, and severe lesion calcification. For the 32% of patients <65 years old with left ventricular ejection fraction >30% and without shock, the prevalence of these adverse risk factors was low. No periprocedural deaths were observed in this low-risk subset, and the 1-year mortality was only 3.4%. Conclusions Patients undergoing unprotected LMT PCI have frequent serious comorbidities and consequently have high event rates. PCI may be an alternative to CABG for a select proportion of elective patients and may also be appropriate for highly symptomatic inoperable patients. Meticulous follow-up of hospital survivors is required because of the rather high mortality during the first few months after treatment.

Background— Quality improvement efforts have focused on strategies to improve the timeliness of reperfusion therapy in ST-elevation myocardial infarction patients who present to hospitals with and without percutaneous coronary intervention (PCI) capability. We implemented and evaluated a protocol to optimize the timeliness of reperfusion therapy and to coordinate systems of care for a PCI center and 28 regional hospitals located up to 150 miles away across 3 states. Methods and Results— The present study focused on a prospective, observational cohort of 597 patients who presented with ST-segment elevation and within 12 hours of symptom onset to Saint Marys Hospital and 28 regional hospitals up to 150 miles away between May 2004 and December 2006. The Mayo Clinic ST-elevation myocardial infarction protocol implemented strategies to improve timeliness of reperfusion therapy and to coordinate systems of care for transfer between hospitals. The study sample consisted of 258 patients who presented to Saint Marys Hospital and were treated with primary PCI (group A), 105 patients who presented to a regional hospital with symptom onset >3 hours and then were transferred for primary PCI (group B), and 131 patients who presented to a regional hospital with symptom onset <3 hours and were treated with full-dose fibrinolytic therapy (group C). For groups A and B, median door-to-balloon times were 71 and 116 minutes, respectively. Door-to-balloon time <90 minutes was achieved in 75% of group A and 12% of group B. Median door-to-needle time was 25 minutes for group C, and 70% had door-to-needle time <30 minutes. Conclusions— The Mayo Clinic ST-elevation myocardial infarction protocol demonstrates the feasibility of implementing strategies to optimize the timeliness of reperfusion therapy and the times that can be achieved through coordinated systems of care for ST-elevation myocardial infarction patients presenting to a PCI center (Saint Marys Hospital) and 28 regional hospitals without PCI capability located up to 150 miles away across 3 states.