Vicken Aharonian

Sodium Bicarbonate vs Sodium Chloride for the Prevention of Contrast Medium–Induced Nephropathy in Patients Undergoing Coronary Angiography: A Randomized Trial

CONTEXT Sodium bicarbonate has been suggested as a possible strategy for prevention of contrast medium-induced nephropathy, a common cause of renal failure associated with prolonged hospitalization, increased health care costs, and substantial morbidity and mortality. OBJECTIVE To determine if sodium bicarbonate is superior to sodium chloride for preventing contrast medium-induced nephropathy in patients with moderate to severe chronic kidney dysfunction who are undergoing coronary angiography. DESIGN, SETTING, AND PATIENTS Randomized, controlled, single-blind study conducted between January 2, 2006, and January 31, 2007, and enrolling 353 patients with stable renal disease who were undergoing coronary angiography at a single US center. Included patients were 18 years or older and had an estimated glomerular filtration rate of 60 mL/min per 1.73 m(2) or less and 1 or more of diabetes mellitus, history of congestive heart failure, hypertension, or age older than 75 years. INTERVENTIONS Patients were randomized to receive either sodium chloride (n = 178) or sodium bicarbonate (n = 175) administered at the same rate (3 mL/kg for 1 hour before coronary angiography, decreased to 1.5 mL/kg per hour during the procedure and for 4 hours after the completion of the procedure). MAIN OUTCOME MEASURE The primary end point was a 25% or greater decrease in the estimated glomerular filtration rate on days 1 through 4 after contrast exposure. RESULTS Median patient age was 71 (interquartile range, 65-76) years, and 45% had diabetes mellitus. The groups were well matched for baseline characteristics. The primary end point was met in 13.3% of the sodium bicarbonate group and 14.6% of the sodium chloride group (relative risk, 0.94; 95% confidence interval, 0.55-1.60; P = .82). In patients randomized to receive sodium bicarbonate vs sodium chloride, the rates of death, dialysis, myocardial infarction, and cerebrovascular events did not differ significantly at 30 days (1.7% vs 1.7%, 0.6% vs 1.1%, 0.6% vs 0%, and 0% vs 2.2%, respectively) or at 30 days to 6 months (0.6% vs 2.3%, 0.6% vs 1.1%, 0.6% vs 2.3%, and 0.6% vs 1.7%, respectively) (P > .10 for all). CONCLUSION The results of this study do not suggest that hydration with sodium bicarbonate is superior to hydration with sodium chloride for the prevention of contrast medium-induced nephropathy in patients with moderate to severe chronic kidney disease who are undergoing coronary angiography. TRIAL REGISTRATION clinicaltrials.gov Identifier: NCT00312117.

Spontaneous coronary dissection: A cluster of cases with this rare finding

Spontaneous coronary dissection is a rare entity. It has been reported to be usually fatal, with greater than an 80% mortality rate. From April 1990 through March 1993, 10 patients had spontaneous coronary dissection. This is a significant increase in the incidence of this diagnosis, with only one prior case at this institution in 1983 (p < 0.001). All of the patients survived. Of the 10 patients, eight were women, and seven of those were premenopausal. Only one was post partum. Acute myocardial infarction was the presenting condition in nine patients. Three patients had spontaneous dissections involving two arteries. Only one patient had associated atherosclerotic coronary artery disease. Surgery was required for continued symptoms in three patients, with difficulty grafting the dissected artery in two. Nine patients have no symptoms, and one has class II angina. With aggressive medical therapy the prognosis of patients with spontaneous coronary dissection may not be as dismal as previously reported.

Long-Term Outcomes by Clopidogrel Duration and Stent Type in a Diabetic Population With De Novo Coronary Artery Lesions

OBJECTIVES The purpose of this study was to determine whether long-term clinical outcomes differed between bare-metal stents (BMS) and drug-eluting stents (DES) by duration of clopidogrel use among diabetic patients. BACKGROUND There is concern that DES are associated with late adverse events such as death and myocardial infarction (MI) secondary to stent thrombosis. However, data on outcomes in diabetic patients remain limited. METHODS We identified 749 patients with diabetes mellitus who underwent stent implantation with either BMS (n = 251) or DES (n = 498) from October 2002 to December 2004. We performed survival analysis on the full cohort and on those event-free from death, MI, or repeat revascularization at 6 months (n = 671). RESULTS By clopidogrel duration, the event rate for death or MI was 3.2% in the >9-month group, 9.4% in the 6- to 9-month group, and 16.5% in the <6-month group, p < 0.001. For death alone, the event rate was 0.5% in the >9-month group, 4.3% in the 6- to 9-month group, and 10.0% in the <6-month group, p < 0.001. When taking BMS clopidogrel non-users as a referent in the multivariate analysis, the hazard ratio (95% confidence interval [CI]) for death and nonfatal MI for DES clopidogrel users, DES clopidogrel nonusers, and BMS clopidogrel users were: HR 0.22 (95% CI 0.08 to 0.62, p = 0.005), HR 0.39 (95% CI 0.13 to 1.13, p = 0.08), and HR 0.25 (95% CI 0.08 to 0.81, p = 0.02), respectively. CONCLUSIONS Longer duration of clopidogrel use was associated with a lower incidence of death or MI in both the BMS and DES groups. Among clopidogrel nonusers, the incidence of death/MI or death did not differ by stent type.

Haemodynamic-guided fluid administration for the prevention of contrast-induced acute kidney injury: the POSEIDON randomised controlled trial

BACKGROUND The administration of intravenous fluid remains the cornerstone treatment for the prevention of contrast-induced acute kidney injury. However, no well-defined protocols exist to guide fluid administration in this treatment. We aimed to establish the efficacy of a new fluid protocol to prevent contrast-induced acute kidney injury. METHODS In this randomised, parallel-group, comparator-controlled, single-blind phase 3 trial, we assessed the efficacy of a new fluid protocol based on the left ventricular end-diastolic pressure for the prevention of contrast-induced acute kidney injury in patients undergoing cardiac catheterisation. The primary outcome was the occurrence of contrast-induced acute kidney injury, which was defined as a greater than 25% or greater than 0·5 mg/dL increase in serum creatinine concentration. Between Oct 10, 2010, and July 17, 2012, 396 patients aged 18 years or older undergoing cardiac catheterisation with an estimated glomerular filtration rate of 60 mL/min per 1·73 m(2) or less and one or more of several risk factors (diabetes mellitus, history of congestive heart failure, hypertension, or age older than 75 years) were randomly allocated in a 1:1 ratio to left ventricular end-diastolic pressure-guided volume expansion (n=196) or the control group (n=200) who received a standard fluid administration protocol. Four computer-generated concealed randomisation schedules, each with permuted block sizes of 4, were used for randomisation, and participants were allocated to the next sequential randomisation number by sealed opaque envelopes. Patients and laboratory personnel were masked to treatment assignment, but the physicians who did the procedures were not masked. Both groups received intravenous 0·9% sodium chloride at 3 mL/kg for 1 h before cardiac catheterisation. Analyses were by intention to treat. Adverse events were assessed at 30 days and 6 months and all such events were classified by staff who were masked to treatment assignment. This trial is registered with ClinicalTrials.gov, number NCT01218828. FINDINGS Contrast-induced acute kidney injury occurred less frequently in patients in the left ventricular end-diastolic pressure-guided group (6·7% [12/178]) than in the control group (16·3% [28/172]; relative risk 0·41, 95% CI 0·22-0·79; p=0·005). Hydration treatment was terminated prematurely because of shortness of breath in three patients in each group. INTERPRETATION Left ventricular end-diastolic pressure-guided fluid administration seems to be safe and effective in preventing contrast-induced acute kidney injury in patients undergoing cardiac catheterisation. FUNDING Kaiser Permanente Southern California regional research committee grant.

Bifurcation stenting with drug-eluting stents: a systematic review and meta-analysis of randomised trials.

AIMS We sought to determine if outcomes differ between provisional (elective side branch stenting) compared to a routine two-stent strategy (mandatory side branch stenting) for the treatment of bifurcation stenoses of the coronary arteries using drug-eluting stents. METHODS AND RESULTS We searched Medline, EMBASE, and the Cochrane library from January 2000 to February 2009 for studies comparing the provisional and two-stent strategies. Six randomised controlled trials, including 1,641 patients, were identified. The relative risk (95% confidence interval) for death, MI, target lesion revascularisation, and stent thrombosis within 1-year of the index procedure for a provisional vs. two-stent strategy were 1.12 (0.42-3.02), 0.57 (0.37-0.87), 0.91 (0.61-1.35), and 0.56 (0.23-1.35), respectively. By quantitative coronary angiography, there was no difference in the difference in means (95% CI) between the provisional and two-stent strategies for percent diameter stenosis (95% CI) in the main vessel or side branch, -1.08 (-2.91 to 0.74) and 1.30 (-3.35 to 5.96), respectively. CONCLUSION While death, stent thrombosis, and restenosis were similar between the treatment groups, MI was more common with the two-stent strategy. Thus, compared to a routine two-stent strategy, provisional stenting yields similar efficacy with superior safety and lower costs.

Prevalence of subclavian artery stenosis in patients with peripheral vascular disease

Internal mammary arteries (IMA) as conduits in coronary artery bypass grafting are superior to saphenous vein grafts. If there is subclavian artery stenosis (SAS) proximal to the IMA graft, impairment of flow to the IMA may occur. If the stenosis is severe, retrograde flow from the grafted coronary artery to the brachial artery may lead to angina. Following the identification of 2 cases of angina secondary to subclavian artery stenosis at their institution, the authors prospectively performed arch angiography in a cohort of patients with manifestations of periph eral vascular disease undergoing diagnostic coronary angiography to assess the prevalence of subclavian stenosis. Fifty-two patients were enrolled in the protocol, with 48 patients having technically acceptable studies. Of these 48, 41.6% had measurable stenosis of at least one of the brachiocephalic arteries, with 35% of patients with at least a 30% stenosis of the left subclavian artery and 18.7% with more than 50% stenosis. They conclude that patients with significant peripheral vascular disease undergoing coronary angiography who are potential candidates for revascularization may benefit from arch angiography as part of their initial evaluation.

Community practice of primary angioplasty for myocardial infarction.

Results obtained with primary angioplasty at the community level do not duplicate the results of the published trials. Major changes in current community practice patterns are needed to achieve the success rates of the published trials.

Outcomes in the Randomized CoreValve US Pivotal High Risk Trial in Patients With a Society of Thoracic Surgeons Risk Score of 7% or Less

Importance Transcatheter aortic valve replacement (TAVR) is now a well-accepted alternative to surgical AVR (SAVR) for patients with symptomatic aortic stenosis at increased operative risk. There is interest in whether TAVR would benefit patients at lower risk. Objective The Society of Thoracic Surgeons Predicted Risk of Mortality (STS PROM) has trended downward in US TAVR trials and the STS/American College of Cardiology Transcatheter Valve Therapy Registry. We hypothesized that if the Society of Thoracic Surgeons Predicted Risk of Mortality (STS PROM) alone is sufficient to define decreased risk, the contribution to survival based on the degree of invasiveness of the TAVR procedure will decrease, making it more difficult to show improved survival and benefit over SAVR. Design, Setting, and Participants The CoreValve US Pivotal High Risk Trial was a multicenter, randomized, noninferiority trial. This retrospective analysis evaluated patients who underwent an attempted implant and had an STS PROM of 7% or less. The trial was performed at 45 US sites. Patients had severe aortic stenosis and were at increased surgical risk based on their STS PROM score and other risk factors. Interventions Eligible patients were randomly assigned (1:1) to self-expanding TAVR or to SAVR. Main Outcomes and Measures We retrospectively stratified patients by the overall median STS PROM score (7%) and analyzed clinical outcomes and quality of life using the Kansas City Cardiomyopathy Questionnaire in patients with an STS PROM score of 7% or less. Results The mean (SD) ages were 81.5 (7.6) years for the TAVR group and 81.2 years (6.6) for the SAVR group. A little more than half were men (57.9% in the TAVR group and 55.8% in the SAVR group). Of 750 patients who underwent attempted implantation, 383 (202 TAVR and 181 SAVR) had an STS PROM of 7% or less (median [interquartile range]: TAVR, 5.3% [4.3%-6.1%]; SAVR, 5.3% [4.1%-5.9%]). Two-year all-cause mortality for TAVR vs SAVR was 15.0% (95% CI, 8.9-10.0) vs 26.3% (95% CI, 19.7-33.0) (log rank P = .01). The 2-year rate of stroke for TAVR vs SAVR was 11.3% vs 15.1% (log rank P = .50). Quality of life by the Kansas City Cardiomyopathy Questionnaire summary score showed significant and equivalent increases in both groups at 2 years (mean [SD] TAVR, 20.0 [25.0]; SAVR, 18.6 [23.6]; P = .71; both P < .001 compared with baseline). Medical benefit, defined as alive with a Kansas City Cardiomyopathy Questionnaire summary score of at least 60 and a less than 10-point decrease from baseline, was similar between groups at 2 years (TAVR, 51.0%; SAVR, 44.4%; P = .28). Conclusions and Relevance Self-expanding TAVR compares favorably with SAVR in high-risk patients with STS PROM scores traditionally considered intermediate risk. Trial Registration Clinicaltrials.gov Identifier: NCT01240902.

Discontinuation of Long-Term Clopidogrel Therapy Is Associated With Death and Myocardial Infarction After Saphenous Vein Graft Percutaneous Coronary Intervention

OBJECTIVES This study sought to examine the pattern of death and myocardial infarction (MI) after clopidogrel cessation in patients undergoing percutaneous coronary intervention (PCI) of the saphenous vein graft (SVG). BACKGROUND The timing and incidence of adverse events by different durations of clopidogrel therapy after SVG PCI remain unknown. METHODS This is a cohort study of patients undergoing SVG PCI between 2000 and 2009, followed for all-cause mortality or MI after stopping clopidogrel. Incidence rates were calculated across different time periods after clopidogrel cessation. Adjusted incidence rate ratios (IRR) were calculated with multivariable regression (piecewise exponential and Poisson). RESULTS There were 603 patients who underwent SVG PCI, of which 411 were event-free at the time of clopidogrel cessation. The incidence rate (95% confidence interval: [CI])/1,000 person-days of death or MI after stopping clopidogrel in the time intervals of 0 to 90 days, 91 to 365 days, and 1 to 2 years were 1.26 (95% CI: 0.93 to 1.70), 0.41 (95% CI: 0.30 to 0.56), and 0.41 (95% CI: 0.30 to 0.55), respectively. In multivariable analyses, the overall IRR (95% CI) for death or MI in the 0- to 90-day interval after stopping clopidogrel compared with the 91- to 365-day interval was 2.58 (95% CI: 1.64 to 4.07). Similar results were observed over a broad range of clopidogrel treatment durations (<6 months, 6 months to 1 year, 1 to 2 years, or >2 years). The results were also consistent across subgroups, including sex, stent type, stent diameter, PCI period, and diabetes status. When death alone was evaluated, there remained a significant increase in the event rate in the 0- to 90-day interval compared with the 91- to 365-day interval (IRR: 2.33; 95% CI: 1.32 to 4.11). CONCLUSIONS A clustering of events was observed in the initial 0 to 90 days after clopidogrel cessation in all treatment durations of clopidogrel investigated after SVG PCI. These results might have important implications in high-risk cohorts undergoing PCI. Additional studies are needed to elucidate the mechanisms underlying the early clustering of events after clopidogrel cessation.

Restenosis in intervened coronaries with hyperhomocysteinemia (RICH)

BACKGROUND Controversy exists regarding the contribution made by elevated serum homocysteine evels in raising the risk of restenosis after percutaneous coronary interventions. The objective of this study was to determine whether elevated homocysteine evels increase the risk of restenosis. METHODS Two hundred and two consecutive patients undergoing percutaneous coronary intervention with stents on previously nonintervened native coronary arteries were eligible for enrollment in the study. Before the percutaneous coronary intervention, a fasting serum homocysteine evel was drawn. Patients were followed-up by their primary cardiologists for recurrence of symptoms. Those patients who had a recurrence of anginal symptoms consistent with clinical restenosis were referred for a repeat angiogram. All other patients were followed-up medically. The homocysteine evels of the patients who had repeat angiography for recurrent symptoms were compared to those who were followed-up medically. RESULTS Age, stent ength, stent diameter, and homocysteine evels were all associated with an increased risk of restenosis in the univariate analysis. In the multiple ogistic regression model, the only variable that remained significant in relation to an increased risk of restenosis was homocysteine. There was a significant difference in the mean homocysteine evels between the restenosis group (13.7 micromol/L) and those without restenosis (9.6 micromol/L; P <.0001). A homocysteine evel > or =11.1 micromol/L was identified as the best threshold for an increased risk of restenosis with a sensitivity of 75.0% and specificity of 76.9% (OR 6.5, CI 2.3-18.6; P =.0004). CONCLUSION This study demonstrates that elevated homocysteine evels strongly correlate with an increased risk of restenosis.