Tarun W. Dasari

Drug eluting versus bare metal stents in cardiac allograft vasculopathy

Background: Cardiac allograft vasculopathy (CAV) is a distinct pathological condition characterized by diffuse and progressive arteriopathy and it is an important determinant of long‐term graft survival. Definitive CAV treatment is retransplantation but palliation with stenting might temporarily alleviate it. The benefit of drug eluting stents (DES) over bare metal stents (BMS) in the treatment of such lesions is debatable. We therefore sought to do a literature search to review the available evidence comparing DES to BMS. Methods: We conducted Pub Med, EMBASE, Cochrane database review, Web of Science search of studies comparing DES with BMS in CAV. Available studies were retrospective in nature with either direct comparison groups (n = 5) or historical controls (n = 1). The main outcomes analyzed were in stent restenosis (ISR) during follow‐up and clinical outcomes. Results: A total of 312 patients from six studies were included in the review (1995–2007). Most commonly used DES were sirolimus eluting stent. DES appeared to reduce the long‐term risk of ISR compared with BMS. Three of the five studies showed a statistically significant reduction in ISR at 12 months while the one study assessing ISR at 6 months showed no significant difference. Clinical endpoints such as death and major adverse cardiac events were not statistically different. Conclusion: DES appear to reduce the incidence of ISR in CAV as compared with BMS. Prospective randomized clinical trials are needed to determine the clinical benefit of DES beyond a reduction in ISR.

Pharmacomechanical Thrombolysis of Acute and Chronic Symptomatic Deep Vein Thrombosis: A Systematic Review of Literature:

Pharmacomechanical thrombolysis (PMT) is an emerging treatment option for symptomatic deep vein thrombosis (DVT). This may obviate the need for systemic or catheter-directed thrombolysis. PubMed, EMBASE, and Cochrane database search of PMT in acute and chronic symptomatic DVT was undertaken. Baseline demographic and clinical characteristics, procedural details, DVT characteristics, and procedural and clinical outcomes are presented. A total of 8 case series (n = 2528; 1998-2009) qualified for inclusion. Lower extremity symptomatic DVTs constituted the majority of the cases (>80%). Both acute (<14 days) and chronic (>14 days) DVTs were included. Procedural success was 59% to 100% and catheter-directed thrombolysis was used as an adjunct in 16% to 53%. No deaths or major bleeding complications were reported. Pharmacomechanical thrombolysis leads to the immediate resolution of clinical symptoms of DVT in the majority of patients. Pharmacomechanical thrombolysis may be a safe and novel method, when appropriate expertise and resources are available, for the treatment of symptomatic acute and chronic DVT.

Impact of Time of Presentation on Process Performance and Outcomes in ST-Segment–Elevation Myocardial Infarction A Report From the American Heart Association: Mission Lifeline Program

Background—Prior studies demonstrated that patients with ST-segment–elevation myocardial infarction presenting during off-hours (weeknights, weekends, and holidays) have slower reperfusion times. Recent nationwide initiatives have emphasized 24/7 quality care in ST-segment–elevation myocardial infarction. It remains unclear whether patients presenting off-hours versus on-hours receive similar quality care in contemporary practice. Methods and Results—Using Acute Coronary Treatment and Intervention Outcomes Network-Get With The Guidelines (ACTION-GWTG) database, we examined ST-segment–elevation myocardial infarction performance measures in patients presenting off-hours (n=27 270) versus on-hours (n=15 972; January 2007 to September 2010) at 447 US centers. Key quality measures assessed were aspirin use within first 24 hours, door-to-balloon time, door-to-ECG time, and door-to-needle time. In-hospital risk-adjusted all-cause mortality was calculated. Baseline demographic and clinical characteristics were similar. Aspirin use within 24 hours approached 99% in both groups. Among patients undergoing primary percutaneous coronary intervention (n=41 979; 97.1%), median door-to-balloon times were 56 versus 72 minutes (P<0.0001) for on-hours versus off-hours. The proportion of patients achieving door-to-balloon time ⩽90 minutes was 87.8% versus 79.2% (P<0.0001), respectively. There were no differences attaining door-to-ECG time ⩽10 minutes (73.4% versus 74.3%, P=0.09) and door-to-needle time ⩽30 minutes (62.3% versus 58.7%; P=0.44) between on-hours versus off-hours. Although in-hospital all-cause mortality was similar (4.2%) in both groups, the risk-adjusted all-cause mortality was higher for patients presenting off-hours (odds ratio, 1.13; 95% confidence interval, 1.02–1.26). Conclusions—In contemporary community practice, achievement of quality performance measures in patients presenting with ST-segment–elevation myocardial infarction was high, regardless of time of presentation. Door-to-balloon time was, however, slightly delayed (by an average of 16 minutes), and risk-adjusted in-hospital mortality was 13% higher in patients presenting off-hours.

Systematic Review of Effectiveness of Oral Sirolimus After Bare-Metal Stenting of Coronary Arteries for Prevention of In-Stent Restenosis

Neointimal hyperplasia after percutaneous coronary intervention is a major determinant of in-stent restenosis (ISR). Drug-eluting stents (DES) mitigate neointimal hyperplasia and thereby lead to a lower rate of ISR compared with bare-metal stents (BMS). Recent studies have demonstrated that short-term use of oral sirolimus after BMS leads to a significant reduction in ISR. We therefore sought to do a systematic review of studies to determine the angiographic and clinical benefits of early short-term use of oral sirolimus after BMS of native coronary arteries. We conducted PubMed, Embase, Cochrane database review, and Web of Science search of studies comparing oral sirolimus after BMS to BMS alone or DES. Outcomes analyzed were ISR and target lesion revascularization (TLR) as well as major adverse cardiovascular events. A total of 488 patients from 4 studies were included in the review (2006 to 2010). Three studies, comparing BMS alone versus BMS plus oral sirolimus, demonstrated significant reduction in ISR in the oral sirolimus group. Two of these studies also demonstrated significant reduction in TLR at 6-12 month follow-up. The fourth study comparing BMS plus oral sirolimus versus DES showed a lower but nonsignificant reduction in TLR in addition to significant cost saving in the group treated with oral sirolimus. In conclusion, our systematic review demonstrates that early short-term systemic use of sirolimus after BMS resulted in a significant reduction in ISR and TLR. In addition, ISR rates were comparable to DES with the added benefit of cost saving.

Non-eligibility for reperfusion therapy in patients presenting with ST-segment elevation myocardial infarction: Contemporary insights from the National Cardiovascular Data Registry (NCDR)

BACKGROUND Reperfusion therapy is lifesaving in patients presenting with ST-segment elevation myocardial infarction (STEMI). Contemporary data describing the characteristics and outcomes of patients presenting with STEMI not receiving reperfusion therapy are lacking. METHODS Using the ACTION Registry-GWTG database, we examined 219,726 STEMI patients (January 2007-December 2013) at 721 percutaneous coronary intervention (PCI)-capable hospitals in United States. Clinical characteristics and in-hospital outcomes were stratified by those who underwent reperfusion (n = 188,200; 86%), those who did not undergo reperfusion with a reason for ineligibility (n = 27,179; 12%), and those without reperfusion but had no reason for ineligibility (n = 4,347; 2%). RESULTS Compared with STEMI patients receiving reperfusion therapy, the nonreperfusion groups were older, were more often female, and had higher rates of hypertension, diabetes, prior myocardial infarction, prior stroke, atrial fibrillation, and left bundle-branch block and heart failure on presentation. The major reason for reperfusion noneligibility was coronary anatomy not suitable for PCI (33%). Presence of 3-vessel coronary disease was more common in the nonreperfusion groups (with or without a documented reason) compared with reperfusion group (38% and 36% vs 26%, P < .001, respectively). In-hospital mortality was higher in patients not receiving reperfusion therapy with or without a documented reason compared with the reperfusion group (adjusted odds ratio [95% CI] 1.88 [1.78-1.99] and 1.37 [1.21-1.57], respectively). CONCLUSION Most patients with STEMI not receiving reperfusion therapy had a documented reason. Coronary anatomy not suitable for PCI was the major contributor to ineligibility. In-hospital mortality was higher in patients not receiving reperfusion therapy.

Clot Strength is Negatively Associated with Ambulatory Function in Patients with Peripheral Artery Disease and Intermittent Claudication

Peripheral artery disease (PAD) is associated with exercise impairment and greater thrombotic risk. We investigated whether clot formation and platelet aggregation assessed by thromboelastography and light-transmission aggregometry correlate with the severity of symptomatic PAD assessed by ambulatory function measures. We studied 40 symptomatic patients with PAD in whom severity of disease was assessed using ankle–brachial index, peak walking time (PWT), claudication onset time, peak oxygen uptake, daily ambulatory activity, and walking impairment questionnaire (WIQ) scores. Clot strength correlated negatively with peak oxygen uptake, PWT, WIQ distance, and stair-climbing scores. Time to clot formation did not correlate with exercise parameters. Platelet aggregation was negatively correlated with WIQ distance score and was positively correlated with PWT and peak oxygen uptake. In conclusion, clot strength and platelet aggregation correlated with objective and self-perceived ambulatory measures. Patients with PAD having more severe walking impairment may be likely to form stronger clots.

Clinical characteristics and in hospital outcomes of heart transplant recipients with allograft vasculopathy undergoing percutaneous coronary intervention: Insights from the National Cardiovascular Data Registry

BACKGROUND Cardiac allograft vasculopathy is a major cause of morbidity and mortality following heart transplantation. Large multicenter studies evaluating the clinical characteristics and inhospital outcomes of heart transplant recipients undergoing percutaneous coronary intervention (PCI) are lacking. OBJECTIVE To evaluate the clinical characteristics, treatment patterns and inhospital outcomes of heart transplant recipients undergoing PCI compared to general population. METHODS We analyzed 1,897,328 patients from the National Cardiovascular Data Registry CathPCI registry who underwent PCI of at least 1 native vessel between July 2009 and December 2013 from 1,477 centers, of which 542 patients (0.03%) were heart transplant recipients. Clinical characteristics were evaluated and, after 1:4 propensity matching, inhospital outcomes were compared between 538 heart transplant patients and 2,128 non-transplant patients. RESULTS Transplant recipients undergoing PCI had a higher prevalence of diabetes, dyslipidemia and peripheral vascular disease; lower prevalence of angina, acute coronary syndrome, abnormal noninvasive functional study, and type C coronary lesions compared to the non-transplant PCI population. After propensity matching, all-cause inhospital mortality was similar between transplant and non-transplant groups (1.3% vs 1.0%; OR, 1.21; 95% CI, 0.54-2.67). CONCLUSION This is the largest series to date outlining the characteristics of heart transplant recipients undergoing PCI. Similar inhospital outcomes were noted in heart transplant recipients compared to the general population. Further studies evaluating long-term outcomes are warranted.

A case of critical aortic stenosis masquerading as acute coronary syndrome.

Serum cardiac troponins I and T are reliable and highly specific markers of myocardial injury. Studies have shown that at least 20% of patients with severe aortic stenosis have detectable serum troponins. This case report describes a patient who presented as suspected acute coronary syndrome with markedly elevated troponin levels, who was later found to have normal coronaries and critical aortic stenosis. This case highlights the need for comprehensive and accurate physical examination in patients who present with angina. Critical aortic stenosis may cause such severe subendocardial ischemia as to cause marked elevation in cardiac markers and mimic an acute coronary syndrome. Careful physical examination will lead to an earlier use of non invasive techniques, such as echocardiography to confirm the correct diagnosis and the avoidance of inappropriate treatments such as intravenous nitroglycerin and glycoprotein IIb/IIIa inhibitors.

Internal Mammary Artery Graft Dissection: A Case-Based Retrospective Study and Brief Review

The left internal mammary artery is the preferred graft for treating left anterior descending coronary artery disease. Dissection is a rare but grave sequela of internal mammary artery graft angiography. The available medical literature is scant, perhaps as a result of under-reporting. We report a case in which dissection of the internal mammary artery graft occurred during diagnostic angiography, and we discuss its management. In addition, we review the available literature and provide a retrospective analysis of the data from our own catheterization laboratory. In our single-center analysis of 542 cases of selective internal mammary artery graft angiography, we found only the single case of internal mammary artery graft dissection (0.2%) that we report here. Our review of the literature revealed 7 reported cases of internal mammary artery graft dissection, 3 of which were iatrogenic. There were no identifiable risk factors for such dissection. After treatment with angioplasty and stenting, all patients had good outcomes during follow-up.

Is risk factor control and guideline-based medical therapy optimal in patients with nonobstructive coronary artery disease? A Veterans Affairs study.

Background:Aggressive risk factor modification using evidence-based secondary prevention strategies is recommended in coronary artery disease (CAD). Utilization of such strategies was compared in patients with nonobstructive CAD (NOCAD) and obstructive CAD (OCAD). Methods:Patients undergoing coronary angiography (excluding normal coronary angiograms), between January 2006 and June 2006, at the Veterans Affairs Medical Center were included. Demographic, clinical and treatment data were compared between the groups at baseline and 1 year. Results:Of the 354 patients who underwent coronary angiography, 222 (63%) had follow-up data available at 12 ± 2 months. The mean age in the NOCAD (n = 119) and OCAD (n = 103) groups was similar. There was a lower prevalence of hypertension and heart failure (P < 0.05) in the NOCAD group. Compared with the OCAD group, aspirin use was similar but statin use was lower in the NOCAD group (P = 0.008). At 1 year, statin use (P = 0001) and angiotensin-converting enzyme inhibitor/angiotensin receptor blocker use (P = 0.001) were significantly lower, whereas the use of aspirin was numerically lower (P = 0.06) in the NOCAD group. Mean low-density lipoprotein cholesterol levels were at goal (<100 mg/dL) in the NOCAD group at baseline and 1 year, whereas the same slightly worsened in the OCAD group at 1 year. Conclusions:The use of evidence-based medical therapy is lower in patients with NOCAD compared with those with OCAD. Improved awareness among health care providers and a unified effort to implement secondary prevention strategies may help correct such deficiencies.