Faculty Bibliography

BACKGROUND: Studies demonstrate an increase in radiation exposure with transradial approach (TRA) when compared with transfemoral approach (TFA) for coronary angiography. Given the learning curve associated with TRA, it is not known if this increased radiation exposure to patients is seen when procedures are performed by experienced operators. METHODS: We retrospectively evaluated 1,696 patients who underwent coronary angiography with or without percutaneous coronary intervention (PCI) by experienced operators at a tertiary center from October 2010 to June 2011. Experienced operators were defined as those that perform >75 PCIs/year with >95% of cases performed using the TRA or TFA approach for >/=5 years. The outcomes of interest were dose area product (DAP) and fluoroscopy time (FT). RESULTS: Of the 1,696 patients, 1,382 (81.5%) were performed by experienced femoral operators using TFA and 314 (18.5%) were performed by experienced radial operators using TRA. Most of these cases (65.4%) were diagnostic only (870 TFA and 240 TRA) with both DAP (6040 [3210-8786] vs 5019 [3377-6869] muGy.m, P = .003] and FT [6.2 [4.0-10.3] vs 3.3 [2.6-5.0] minutes, P < .001) significantly higher using TRA versus TFA. For procedures involving PCI, despite similar baseline patient, procedural and lesion characteristics, DAP and FT remained significantly higher using TRA versus TFA (19,649 [11,996-25,929] vs 15,395 [10,078-21,617] muGy.m, P = .02 and 22.1 [13.3-31.0] vs. 13.8 [9.8-20.3] minutes, P < .001). CONCLUSIONS: In a contemporary cohort of patients undergoing coronary angiography by experienced operators, TRA was associated with higher radiation exposure when compared with TFA.

BACKGROUND Dual calcium-channel blocker (CCB) with a dihydropyridine (DHP) and a nondihydropyridine (NDHP) has been proposed for hypertension treatment. However, the safety and efficacy of this approach is not well known. METHODS A MEDLINE/EMBASE/CENTRAL search for randomized clinical trials published on this topic from 1966 to February 2012 was performed. Efficacy outcomes of decrease in systolic (SBP) and diastolic (DBP) blood pressures from baseline, changes in heart rate (HR), and adverse effects were compared between dual CCB therapy vs. DHP or NDHP. SBP, DBP, and HR were expressed as weighted mean deviation (WMD). RESULTS A total of 6 studies with 153 patients were included. Dual CCB produced a significantly greater reduction in SBP (21.6+/-9.2 mmHg) from baseline than DHP (10.3+/-6.3 mmHg (WMD = 10.9 mmHg, P < 0.0001)) or NDHP (8.9+/-4.2 mmHg (WMD = 14.1 mmHg, P = 0.002)). Dual CCB therapy reduced DBP from baseline more than either monotherapy (dual CCB = 17.5+/-10.2 mmHg vs. DHP = 11.6+/-8.7 mmHg, WMD = 5.5 mmHg, P < 0.001; and NDHP = 10.5+/-5.6 mmHg, WMD = 5.3 mmHg, P = 0.03). Dual CCB therapy had significantly lower HR compared to DHP (P < 0.001) but was comparable to NDHP (P = 0.12) (Delta change dual CCB = -4.0+/-3.5 vs. DHP = -2.0+/-1.5 and NDHP = -6.0+/-5.0 beats/min). Dual CCB therapy did not increase adverse effects. CONCLUSIONS Dual CCB therapy lowers blood pressure significantly better than CCB monotherapy, without an increase in adverse events. However, given the lack of long-term outcome data on efficacy and safety, dual CCB therapy should be used with restraint, if at all. Large-scale long-term trials are needed to further evaluate such a strategy.

OBJECTIVE: To compare the long term efficacy and adverse events of dual blockade of the renin-angiotensin system with monotherapy. DESIGN: Systematic review and meta-analysis. DATA SOURCES: PubMed, Embase, and the Cochrane central register of controlled trials, January 1990 to August 2012. STUDY SELECTION: Randomised controlled trials comparing dual blockers of the renin-angiotensin system with monotherapy, reporting data on either long term efficacy (>/=1 year) or safety events (>/=4 weeks), and with a sample size of at least 50. Analysis was stratified by trials with patients with heart failure versus patients without heart failure. RESULTS: 33 randomised controlled trials with 68 405 patients (mean age 61 years, 71% men) and mean duration of 52 weeks were included. Dual blockade of the renin-angiotensin system was not associated with any significant benefit for all cause mortality (relative risk 0.97, 95% confidence interval 0.89 to 1.06) and cardiovascular mortality (0.96, 0.88 to 1.05) compared with monotherapy. Compared with monotherapy, dual therapy was associated with an 18% reduction in admissions to hospital for heart failure (0.82, 0.74 to 0.92). However, compared with monotherapy, dual therapy was associated with a 55% increase in the risk of hyperkalaemia (P<0.001), a 66% increase in the risk of hypotension (P<0.001), a 41% increase in the risk of renal failure (P=0.01), and a 27% increase in the risk of withdrawal owing to adverse events (P<0.001). Efficacy and safety results were consistent in cohorts with and without heart failure when dual therapy was compared with monotherapy except for all cause mortality, which was higher in the cohort without heart failure (P=0.04 v P=0.15), and renal failure was significantly higher in the cohort with heart failure (P<0.001 v P=0.79). CONCLUSION: Although dual blockade of the renin-angiotensin system may have seemingly beneficial effects on certain surrogate endpoints, it failed to reduce mortality and was associated with an excessive risk of adverse events such as hyperkalaemia, hypotension, and renal failure compared with monotherapy. The risk to benefit ratio argues against the use of dual therapy.

BACKGROUND: Contemporary studies have shown that spontaneous but not procedural myocardial infarction (MI) are related to subsequent mortality. Whether PCI reduces spontaneous (non-procedural) MI is unknown. METHODS AND RESULTS: PUBMED, EMBASE, and CENTRAL were searched for randomized clinical trials (RCTs), until October 2012, comparing PCI with OMT, for stable ischemic heart disease, and reporting MI outcomes - spontaneous non-procedural MI, procedural MI and all MI including procedure related MI. Given the varying length of follow-up between trials, a mixed-effect poisson regression meta-analysis was employed. From 12 RCTs with 37548 patient-years of follow-up, PCI, when compared with OMT alone, was associated with significant lower incident rate ratio (IRR) for spontaneous non-procedural MI (IRR=0.76, 95% CI 0.58-0.99) at the risk of higher procedural MI (IRR=4.11, 95% CI 2.53-6.88) without any difference in all MI (IRR=0.96, 95% CI 0.74-1.21). The point estimate for PCI vs. OMT for all-cause mortality (IRR=0.88, 95% CI 0.75-1.03) and cardiovascular mortality (IRR=0.70, 95% CI 0.44-1.09) paralleled that of spontaneous non-procedural MI (but not procedural or all nonfatal MI) although these were not statistically significant. CONCLUSIONS: PCI compared to OMT reduced spontaneous MI at the risk of procedural MI without any difference in all MI. Consistent with prior studies showing that spontaneous MI but not procedural MI are related to subsequent mortality, in the present report the point estimate for reduced mortality with PCI compared to OMT paralleled the prevention of spontaneous MI with PCI. Further studies are needed to determine whether these associations are causal.