Five-Year Results of Coronary Artery Bypass Grafting With or Without Carotid Endarterectomy in Patients With Asymptomatic Carotid Artery Stenosis: CABACS RCT.

BACKGROUND: In patients with coronary artery disease and concomitant asymptomatic severe carotid stenosis, combined simultaneous coronary artery bypass grafting (CABG) and carotid endarterectomy (CEA) has been widely performed despite lack of evidence from randomized trials. We recently showed that the risk of stroke or death within 30 days was higher following CABG+CEA compared with CABG alone. Here, we report long-term outcomes following CABG with versus without CEA. METHODS: The CABACS (Coronary Artery Bypass Graft Surgery in Patients With Asymptomatic Carotid Stenosis Study) is a randomized, controlled, multicenter, open trial. Patients with asymptomatic severe (≥70%) carotid stenosis undergoing CABG were allocated either CABG+CEA or CABG alone, and follow-up was 5 years. Major secondary end points included nonfatal stroke or death, any death and any nonfatal stroke. Due to low recruitment, the study was stopped prematurely after randomization of 127 patients in 17 centers. RESULTS: By 5 years, the rate of stroke or death did not significantly differ between groups (CABG+CEA 40.6% [95% CI, 0.285-0.536], CABG alone 35.0% [95% CI, 0.231-0.484]; P=0.58). Higher albeit statistically nonsignificant rates of nonfatal strokes occurred at any time following CABG+CEA versus CABG alone (1 year: 19.3% versus 7.1%, P=0.09; 5 years: 29.4% versus 18.8%, P=0.25). All-cause mortality up to 5 years was similar in both groups (CABG+CEA: 25.4% versus CABG alone: 23.3%, hazard ratio, 1.148 [95% CI, 0.560-2.353]; P=0.71). Subgroup analyses did not reveal any significant effect of age, sex, preoperative modified Rankin Scale and center on outcome events. CONCLUSIONS: During 5-years follow-up, combined simultaneous CABG+CEA was associated with a higher albeit statistically nonsignificant rate of stroke or death compared with CABG alone. This was mainly due to a nonsignificantly higher perioperative risk following CABG+CEA. Since the power of our study was not sufficient, no significant effect of either procedure could be observed at any time during follow-up. REGISTRATION: URL: http://www.controlled-trials.com; Unique identifier: ISRCTN13486906.

Safety of Simultaneous Coronary Artery Bypass Grafting and Carotid Endarterectomy Versus Isolated Coronary Artery Bypass Grafting: A Randomized Clinical Trial.

BACKGROUND AND PURPOSE: The optimal operative strategy in patients with severe carotid artery disease undergoing coronary artery bypass grafting (CABG) is unknown. We sought to investigate the safety and efficacy of synchronous combined carotid endarterectomy and CABG as compared with isolated CABG. METHODS: Patients with asymptomatic high-grade carotid artery stenosis ≥80% according to ECST (European Carotid Surgery Trial) ultrasound criteria (corresponding to ≥70% NASCET [North American Symptomatic Carotid Endarterectomy Trial]) who required CABG surgery were randomly assigned to synchronous carotid endarterectomy+CABG or isolated CABG. To avoid unbalanced prognostic factor distributions, randomization was stratified by center, age, sex, and modified Rankin Scale. The primary composite end point was the rate of stroke or death at 30 days. RESULTS: From 2010 to 2014, a total of 129 patients were enrolled at 17 centers in Germany and the Czech Republic. Because of withdrawal of funding after insufficient recruitment, enrolment was terminated early. At 30 days, the rate of any stroke or death in the intention-to-treat population was 12/65 (18.5%) in patients receiving synchronous carotid endarterectomy+CABG as compared with 6/62 (9.7%) in patients receiving isolated CABG (absolute risk reduction, 8.8%; 95% confidence interval, -3.2% to 20.8%; PWALD=0.12). Also for all secondary end points at 30 days and 1 year, there was no evidence for a significant treatment-group effect although patients undergoing isolated CABG tended to have better outcomes. CONCLUSIONS: Although our results cannot rule out a treatment-group effect because of lack of power, a superiority of the synchronous combined carotid endarterectomy+CABG approach seems unlikely. Five-year follow-up of patients is still ongoing. CLINICAL TRIAL REGISTRATION: URL: https://www.controlled-trials.com. Unique identifier: ISRCTN13486906.

Cardiovascular characterization of Pkd2(+/LacZ) mice, an animal model for the autosomal dominant polycystic kidney disease type 2 (ADPKD2).

BACKGROUND: Autosomal dominant polycystic kidney disease (ADPKD) is caused by mutations in PKD1 or PKD2. Patients with ADPKD have an increased incidence of cardiac valve abnormalities and left ventricular hypertrophy. Systematic analyses of cardiovascular involvement have so far been performed only on genetically unclassified patients or on ADPKD1 patients, but not on genetically defined ADPKD2 patients. Even existing Pkd1 or Pkd2 mouse models were not thoroughly analyzed in this respect. Therefore, the aim of this project was the noninvasive functional cardiovascular characterization of a mouse model for ADPKD2. METHODS: Pkd2(+/LacZ) mice and wildtype controls were classified into 8 groups with respect to gender, age and genotype. In addition, two subgroups of female mice were analyzed for cardiac function before and during advanced pregnancy. Doppler-echocardiographic as well as histological studies were performed. RESULTS: Doppler-echocardiography did not reveal significant cardiovascular changes. Heart rate and left ventricular (LV) length, LV mass, LV enddiastolic and LV endsystolic diameters did not differ significantly among the various groups when comparing wildtype and knockout mice. There were no significant differences except for a tendency towards higher maximal early and late flow velocities over the mitral valve in old wildtype mice. CONCLUSIONS: Non-invasive phenotyping using ultrasound did not reveal significant cardiovascular difference between adult Pkd2(+/LacZ) and WT mice. Due to the lack of an obvious renal phenotype in heterozygous mice, it is likely that in conventional ADPKD knock out mouse models severe cardiac problems appear too late to be identified during the reduced lifespan of the animals.

Rab6 interacts with the mint3 adaptor protein.

The Rab6 GTPase regulates a retrograde transport route connecting endosomes and the endoplasmic reticulum (ER) via the Golgi apparatus. Recently it was shown that active (GTP-loaded) Rab6A regulates intracellular processing of the amyloid precursor protein (APP). To characterize the role of Rab6A in APP trafficking and to identify effector proteins of the active Rab6A protein, we screened a human placenta cDNA library using the yeast two-hybrid system. We isolated an interacting cDNA clone encoding part of the adaptor protein mint3. The interaction between Rab6A and mint3 is GTP-dependent and requires the complete phosphotyrosine-binding (PTB) domain of the mint protein, which also mediates the association with APP. By confocal microscopy we show that Rab6A, mint3 and APP co-localize at Golgi membranes in HeLa cells. Density gradient centrifugation of cytosolic extracts confirms a common distribution of these three proteins. Our data suggest that mint3 links Rab6A to APP traffic.