Mark A. Apfelbaum

Value of Drug-Eluting Stents in Cardiac Transplant Recipients

Transplant allograft vasculopathy (TAV) was a leading cause of death in cardiac transplant recipients after the first year of transplantation. Whether drug-eluting stents (DESs) performed better than bare-metal stents (BMSs) for the treatment of patients with discrete epicardial stenosis was unknown. The aim was to determine the safety and efficacy of DESs compared with BMSs in the treatment of patients with TAV. Outcomes of 32 patients sequentially treated using DESs for TAV were retrospectively reviewed and compared with a historic cohort of 35 patients treated sequentially with BMSs for TAV. Patients treated with DESs were also compared with age- and gender-matched cardiac transplant controls to determine differences in survival. After adjustment for baseline risk factors, there was no difference in 1-year survival between patients treated with DESs or BMSs for TAV. Restenosis rates at 1 year were 49% in lesions treated using BMSs and 19% in those treated using DESs. Compared with an age- and gender-matched control group of cardiac transplant patients who did not have discrete obstructive epicardial TAV, patients who required treatment with DESs for epicardial obstructive disease had significantly worse survival. In conclusion, treatment of patients with TAV with DESs did not seem to alter the natural deleterious history of this disease process.

In vivo comparison between cardiac allograft vasculopathy and native atherosclerosis using near-infrared spectroscopy and intravascular ultrasound

AIMS The aim was to compare cardiac allograft vasculopathy to native atherosclerosis by near-infrared spectroscopy-intravascular ultrasound (NIRS-IVUS). METHODS AND RESULTS Twenty-seven atherosclerotic (non-transplant) patients and 28 heart transplant recipients undergoing routine surveillance coronary angiography underwent NIRS-IVUS imaging of the left anterior descending coronary artery. In each proximal, middle, and distal coronary artery segment, the maxLCBI4mm [4-mm long segment with maximum lipid core burden index (LCBI)] and corresponding IVUS parameters were compared. MaxLCBI4mm was significantly greater among atherosclerotic patients than the transplant patients in both proximal and middle coronary artery segments, but not in the distal segment. There was a positive linear correlation between maxLCBI4mm and maximum plaque burden in both groups, but atherosclerotic patients demonstrated a smaller maxLCBI4mm than transplant recipients among segments with plaque burden <40%. Among segments with a maximum plaque burden ≥40%, native-atherosclerosis patients had a greater maxLCBI4mm compared with transplant patients (P = 0.015). Calcification was present in 72.9% of native atherosclerosis and 14.7% of transplant segments (P< 0.001). Among the 165 analysed segments, prevalence of lipid-rich plaque (LRP) with superficial attenuation (30.9 vs. 1.2%, P < 0.001) or calcified LRP (13.6 vs. 2.4%, P = 0.03) was significantly greater in native atherosclerosis compared with transplant patients. Conversely, the proportion of segments with non-LRP (46.4 vs. 11.1%, P < 0.001) was higher in transplant patients. CONCLUSION NIRS-IVUS imaging demonstrated early and accelerated lipid accumulation with smaller plaque burden and less calcium in patients after heart transplant when compared with patients with native atherosclerosis.

A rapid-response alphanumeric paging design decreases door-to-balloon times in patients undergoing primary percutaneous coronary intervention for ST elevation acute myocardial infarction.

INTRODUCTION In acute ST elevation myocardial infarction (STEMI), rapid reperfusion of the infarcted artery improves cardiovascular outcomes; however, many hospitals have difficulty achieving recommended times. We hypothesized that a Rapid-Response Alphanumeric Paging Design (RAPiD) would reduce door-to-balloon time for primary percutaneous coronary intervention (PCI) in STEMI. METHODS A chest pain algorithm and interdisciplinary team was established in December 2000. In August 2002, RAPiD was instituted to transmit the diagnosis and location of a STEMI to the chest pain team through a speed-dial button. All patients presenting to our emergency department from February 2002 through July 2003 with STEMI were included. Exclusion criteria included lack of chest pain, cardiopulmonary arrest before PCI, and catheterization or PCI not performed. Outside-referral STEMI, in-patient STEMI, and failed thrombolysis patients were excluded. Data was obtained from medical records. Log transform of door-to-balloon (DTB) times was performed. RESULTS Forty-seven events satisfied inclusion and exclusion criteria with 32 occurring after RAPiD (post-RAPiD). Fifteen events occurred during on-hours (8 am to 7 pm on weekdays). Mean untransformed DTB times pre- and post-RAPiD were 162 +/- 137 (standard deviation) minutes and 112 +/- 41 minutes. The main effects analysis of variance model showed a significant reduction in post-RAPiD DTB time (P = 0.03) with a mean reduction of 26% during off-hours and 20% during on-hours. The post-RAPiD estimate of mean DTB time, derived from the antilog of the log transform, was 96.7 minutes (95% confidence interval, 83.7-111.7). CONCLUSIONS The institution of RAPiD in a hospital with a preexisting chest pain algorithm significantly decreases DTB times so as to satisfy current ACC/AHA guidelines.

Volumetric Intravascular Ultrasound Assessment of Mechanisms and Results of Stent Expansion in Heart Transplant Patients

Percutaneous coronary intervention with stent placement for the treatment of patients with cardiac allograft vasculopathy is common, but data regarding stent behavior in this setting is lacking.

NEW INSIGHTS IN CARDIAC ALLOGRAFT VASCULOPATHY BY NEAR-INFRARED SPECTROSCOPY

Methods: We performed NIRS/IVUS at the time of routine surveillance coronary angiography. NIRS data was transformed into a probability of LRP; pixels with a probability of LRP >0.6 were divided by all viable pixels to generate the lipid-core burden index (LCBI). In each proximal, middle and distal coronary artery segment, the relationship between a history of cellular rejection and maxLCBI4mm (the 4-mm long segment with the maximum LCBI) along with corresponding maximum plaque burden site by IVUS were evaluated.