Faculty Bibliography

Purpose of Review: Stent design continues to evolve with newer generation of stents aimed at improving clinical outcomes. This review compares different generations of stents with a focus on biodegradable polymers and stents and their potential benefits. Recent Findings: Drug-eluting stents (DES) reduce stent thrombosis when compared with bare-metal stents (BMS). However, they are associated with impaired vascular healing/endothelialization and excess very long-term events (beyond 1 year). Much of these events (beyond 1 year) have been attributed to continued inflammation due to the polymer. Biodegradable-polymer drug-eluting stents (BP DES) were designed to overcome this polymer related limitation of first-generation DP DES by combining the benefits of reduced in-stent restenosis seen with DES and the benefits of reduced very-late stent thrombosis and myocardial infarction due to absence of polymer with bare-metal stents (BMS). Earlier generation of BP DES showed superiority over first-generation DP DES but at best non-inferior to second-generation DP DES for clinical outcomes; however, the newer-generation BP DES with ultrathin struts show promise in further reducing clinical outcomes when compared with second-generation DP DES. Whether this is due to the biodegradable polymer or the ultrathin struts continues to be debated. Summary: Biodegradable polymer stents in conjunction with ultrathin struts have shown promise as the next generation of DES; however, additional studies and long-term follow-up are needed to confirm these effects.

BACKGROUND:Central arteriovenous fistula (cAVF) has been investigated as a therapeutic measure for treatment resistant hypertension in patients without advanced chronic kidney disease (CKD). There is considerable experience with the use of arteriovenous fistula (AVF) for hemodialysis in patients with end stage renal disease (ESRD). However, there is sparse data on the blood pressure (BP) effects of an AVF among patients with ESRD. We hypothesized that AVF creation would significantly reduce BP compared to patients who did not have an AVF among patients with ESRD before starting hemodialysis. METHODS:Blood pressures were compared during the 12 months before hemodialysis initiation in 399 patients with an AVF or AV graft created and 4696 patients without either. RESULTS:After propensity score matching 1:2 ratio (AVF to no AVF), repeated measures analysis of variance revealed significant reductions of -1.7 mmHg systolic and -3.9 mmHg diastolic BP 12 months in patients after AVF creation; p=0.025 and p < 0.001, respectively, as compared to those with no AVF. CONCLUSIONS:These findings suggest that AVF creation results in modest BP reduction in patients with pre-dialysis ESRD who require AVF for eventual hemodialysis therapy. Preferential DBP reduction suggest greater work is needed to characterize the ideal patient subset in which to use cAVF for treatment resistant hypertension in those without advanced CKD.

Until recently, intraindividual visit-to-visit variability of cardiovascular risk factors has been dismissed as random fluctuation. This simplistic concept was challenged by demonstrating that visit-to-visit blood pressure variability, independent of average blood pressure, was a powerful risk factor for stroke. Subsequently, variability of other cardiovascular risk factors such as cholesterol, glycemia, and body weight was documented to increase risk independent of their absolute values. Variability of these risk factors has been demonstrated to be a powerful predictor for all-cause and cardiovascular mortality, stroke, coronary artery disease, heart failure, end-stage renal disease, and dementia. With the notable exception of heart rate, cardiovascular risk factors must now be defined by 2 components: the magnitude and duration of sustained risk factor elevation and, equally important, the variability of the same risk factor over time.

BACKGROUND:Patients with diabetes and those with chronic kidney disease (CKD) are at increased risk of cardiovascular events. Everolimus eluting stents (EES) have been shown to be superior to paclitaxel eluting stents (PES) in patients with diabetes. However, it is not known if EES is as beneficial in diabetic patients with CKD compared with those without CKD. METHODS AND RESULTS/RESULTS: = 0.04) such that EES was superior to PES in the non-CKD cohort but not in the CKD cohort. CONCLUSIONS:In subjects with diabetes, CKD is an independent predictor of adverse cardiovascular outcomes including increased risk of death driven largely by non-stent related events. While EES was superior to PES in patients without CKD, this was not the case in those with CKD (Clinical Trials Registry-India number, CTRI/2011/06/001830).