A Novel Approach Using Computed Tomography Angiograms to Predict Sternotomy or Complicated Anastomosis in Patients Undergoing Robotically Assisted Minimally Invasive Direct Coronary Artery Bypass.

OBJECTIVE: Robotically assisted minimally invasive direct coronary artery bypass is an alternative to sternotomy-based surgery in properly selected patients. Identifying the left anterior descending artery when it is deep in the epicardial fat can be particularly challenging through a 5- to 6-cm mini-thoracotomy incision. The objective of this study was to evaluate a technique for predicting conversion to sternotomy or complicated left anterior descending artery anastomosis using preoperative cardiac-gated computed tomography angiograms. METHODS: Retrospective review of 75 patients who underwent robotically assisted minimally invasive direct coronary artery bypass for whom a preoperative computed tomography angiogram was available. The distance from the left anterior descending artery to the myocardium was measured on a standardized "5-chamber" axial computed tomography view. The relative risk of sternotomy or complicated anastomosis was compared between patients whose left anterior descending artery was resting directly on the myocardium (left anterior descending artery to the myocardium distance = 0 mm) with those whose left anterior descending artery was resting above (left anterior descending artery to the myocardium distance > 0 mm). RESULTS: The average left anterior descending artery to the myocardium distance was 3.2 ± 2.6 mm (range = 0-11.5 mm). Fourteen patients (18.7%) had an left anterior descending artery to the myocardium distance of 0 mm. Of the entire group of 75 patients, 6 (8.0%) required conversion to sternotomy. Four others (5.3%) were reported to have a complication with the anastomosis intraoperatively. For patients with left anterior descending artery to the myocardium distance of 0 mm, the relative risk of sternotomy or complicated anastomosis was 18.0 (95% confidence interval = 4.3-75.6, P = 0.0001). CONCLUSIONS: In our experience, patients with left anterior descending artery to the myocardium distance of 0 mm were at significantly higher risk of either conversion to sternotomy or technically challenging anastomosis, with 8 (57.1%) of 14 patients in this group experiencing either end point. This novel measurement may be useful to identify patients who may have anatomy, which is not well suited to the robotically assisted minimally invasive direct coronary artery bypass approach.

A 2-step optical coherence tomography guided therapeutic approach to acute myocardial infarction secondary to stent thrombosis.

UNLABELLED: Myocardial infarction secondary to stent thrombosis has high mortality and recurrence rate. Emergency PCI has high risk of no-reflow. We used a 2-step approach of early recanalization with minimal mechanical intervention followed by delayed PCI 1-2days later guided by Optical Coherence Tomography (OCT). From October 2011 to December 2013, we treated 5 patients with this approach. Time from early recanalization to the delayed definitive PCI was 1day (median, range 1-3days). All the OCT images were diagnostic with a clear view of the underlying structures. SUMMARY: A 2-step approach to treat stent thrombosis appears beneficial with low incidence of peri-procedural thrombosis or no-reflow phenomena during the second step, and superb OCT imaging.

Prognostic implications of prominent R wave in electrocardiographic leads V1 or V2 in patients with acute coronary syndrome.

Although the adverse prognosis of Q-waves on electrocardiogram (ECG) has been demonstrated, the prognostic significance of prominent R wave (PRW) in V1 or V2 across a broad spectrum of acute coronary syndrome (ACS) has not been specifically studied. In the Global Registry of Acute Coronary Events (GRACE) and the Canadian ACS Registry I ECG substudies, admission ECGs were analyzed in an independent core ECG laboratory. PRW was defined as R wave >40 to 50 ms in V1 or V2, R/S ≥1 in V1, or R/S ≥1.5 in V2. Among 11,895 patients with ACS, 495 (4.2%) had PRW; they were less likely to have a history of hypertension or heart failure and had lower GRACE risk scores, but a higher incidence of ST-segment depression (all p ≤0.001). Patients with PRW had similar rates of in-hospital death (2.8% vs 4.1%, respectively, p = 0.15) but lower rates of in-hospital heart failure (8.5% vs 15.2%, respectively, p = 0.02) and 6-month mortality (4.6% vs 8.4%, respectively, p = 0.004). In multivariable analyses, PRW was not a significant independent predictor of in-hospital mortality (adjusted odds ratio = 0.99, 95% confidence interval 0.55 to 1.8) or 6-month mortality (adjusted odds ratio = 0.70, 95% confidence interval 0.43 to 1.15). Among 4,418 patients who underwent coronary angiography, those with PRW had a higher prevalence of left circumflex artery disease (62.5% vs 49.5%, respectively, p = 0.01). In conclusion, across the broad spectrum of patients with ACS, PRW provides no significant additional prognostic utility beyond comprehensive risk assessment using the GRACE risk score. PRW is more frequently associated with left circumflex artery disease.

Feasibility of optical coherence tomography in children with Kawasaki disease and pediatric heart transplant recipients.

BACKGROUND: Optical coherence tomography (OCT) is a high-resolution intravascular imaging technique used in adults. We tested the hypothesis that OCT could identify coronary abnormalities not seen by angiography in children with a history of Kawasaki disease (KD) and pediatric heart transplant (TX) recipients. METHODS AND RESULTS: Patients with KD and TX recipients were evaluated between December 2012 and October 2013 with angiography and OCT (Ilumien System, LightLabs, St Jude Medical, Westford, MA). Modifications were made to the adult OCT protocol to adapt this technique for children. Serial cross-sectional area measurements of the lumen, intima, and media were made. Entire imaging data were analyzed for the presence of qualitative changes. Seventeen children were evaluated (5 patients with KD; 12 TX recipients). In patients with KD, angiography was normal. However, OCT imaging revealed that significant vessel wall abnormalities were present in all children including intimal thickening (intima/lumen cross-sectional area ratio>0.4), loss of the normal layered structure of the vessel wall, white thrombus, calcification, and neovascularization. There was extensive destruction of the internal elastic lamina. In TX recipients, angiography was normal; however, intimal thickening (intima/media cross-sectional area ratio>1) was seen in 9 of 12 patients. The median intima/media cross-sectional area ratio was 1.18. CONCLUSIONS: In this initial experience with OCT in children, we have identified significant coronary abnormalities with OCT that are angiographically silent in children with a history of coronary aneurysms because of KD and in pediatric TX recipients.

Effect on platelet reactivity from a prasugrel loading dose after a clopidogrel loading dose compared with a prasugrel loading dose alone: Transferring From Clopidogrel Loading Dose to Prasugrel Loading Dose in Acute Coronary Syndrome Patients (TRIPLET): a randomized controlled trial.

BACKGROUND: Adding a prasugrel loading dose (LD) to a clopidogrel LD could be desirable because clopidogrel may fail to provide adequate levels of platelet inhibition in patients with acute coronary syndrome undergoing percutaneous coronary intervention. METHODS AND RESULTS: The pharmacodynamic response of prasugrel 60 mg ld alone was compared with prasugrel 60 mg or 30 mg added 24 hours to clopidogrel 600 mg in Transferring From Clopidogrel Loading Dose To Prasugrel Loading Dose In Acute Coronary Syndrome Patients study: a multicenter, randomized, double-blind, double-dummy, 3-arm, parallel, active-comparator controlled study. Two hundred eighty-two patients were randomized to 3 LD strategies: placebo plus prasugrel 60 mg, clopidogrel 600 mg plus prasugrel 60 mg, or clopidogrel 600 mg plus prasugrel 30 mg. Platelet function was assessed using VerifyNow P2Y12 Reaction Units (PRU) immediately before prasugrel LD, and 2, 6, 24, and 72 hours after prasugrel LD in 149 patients with evaluable platelet function studies. At 6 hours after the prasugrel 60 mg LD, the least squares mean (95% confidence interval) difference between placebo/prasugrel 60 mg and clopidogrel 600 mg/prasugrel 60 mg (primary outcome) was 22.2 (-11.0 to 55.5; P=0.19; least squares mean PRU 57.9 versus 35.6, respectively). For clopidogrel 600 mg/prasugrel 30 mg (least squares mean PRU, 53.9), the difference was 3.9 (-28.2 to 36.1; P=0.81) versus placebo/prasugrel 60 mg. No significant differences in PRU were observed at any time point across the 3 groups. There were few bleeding events observed regardless of treatment. CONCLUSIONS: Platelet reactivity with prasugrel 60 mg LD added to clopidogrel 600 mg LD was not significantly different compared with prasugrel 60 mg LD alone in acute coronary syndrome patients undergoing percutaneous coronary intervention. CLINICAL TRIAL REGISTRATION URL: http://www.clinicaltrials.gov. Unique identifier: NCT01115738.

Experience of stenting for atherosclerotic renal artery stenosis in a cardiac catheterization laboratory: technical considerations and complications.

BACKGROUND: Atherosclerotic renal artery (RA) stenosis contributes to hypertension, renal insufficiency and end stage renal disease, and is independently associated with adverse cardiovascular events. Percutaneous renal intervention is efficacious in treating renovascular hypertension and may be effective in stabilizing or improving renal function, thereby reducing cardiovascular risk. However, high rates of procedural complications have been reported. OBJECTIVES: To determine the nature and frequency of complications of percutaneous renal intervention using contemporary techniques and equipment in a high-volume cardiac catheterization laboratory. METHODS: Consecutive patients undergoing attempted RA stenting for atherosclerotic RA stenosis in the cardiac catheterization laboratory at the Vancouver General Hospital (Vancouver, British Columbia) between June 2000 and March 2007 were enrolled in a prospective registry. Baseline clinical characteristics, procedural and technical information, and complications were recorded. RESULTS: A total of 132 RAs were stented in 106 patients during 108 procedures. The procedural success rate was 100%, with no related death, myocardial infarction, nephrectomy or dialysis. Major complications included three pseudoaneurysms (2.8%) and acute deterioration in renal function in six patients (5.5%), although renal function returned to baseline in one patient at 12 months. CONCLUSIONS: RA stenting can be successfully and safely performed using contemporary techniques, and the low complication rates described should be the minimum standard for contemporary trials evaluating RA stenting.

Percutaneous coronary intervention and 30-day mortality: the British Columbia PCI risk score.

OBJECTIVES: To construct a calculator to assess the risk of 30-day mortality following PCI. BACKGROUND: Predictors of 30-day mortality are commonly used to aid management decisions for cardiac surgical patients. There is a need for an equivalent risk-score for 30-day mortality for percutaneous coronary intervention (PCI) as many patients are suitable for both procedures. METHODS: The British Columbia Cardiac Registry (BCCR) is a population-based registry that collects information on all PCI procedures performed in British Columbia (BC). We used data from the BCCR to identify risk factors for mortality in PCI patients and construct a calculator that predicts 30-day mortality. RESULTS: Patients (total n = 32,899) were divided into a training set (n = 26,350, PCI between 2000 and 2004) and validation set (n = 6,549, PCI in 2005). Univariate predictors of mortality were identified. Multivariable logistic regression analysis was performed on the training set to develop a statistical model for prediction of 30-day mortality. This model was tested in the validation set. Variables that were objective and available before PCI were included in the final risk score calculator. The 30-day mortality for the overall population was 1.5% (n = 500). Area under the ROC curve was 90.2% for the training set and 91.1% for the validation set indicating that the model also performed well in this group. CONCLUSIONS: We describe a large, contemporary cohort of patients undergoing PCI with complete follow-up for 30-day mortality. A robust, validated model of 30-day mortality after PCI was used to construct a risk calculator, the BC-PCI risk score, which can be accessed at www.bcpci.org.

Abbreviated infusion of eptifibatide after successful coronary intervention The BRIEF-PCI (Brief Infusion of Eptifibatide Following Percutaneous Coronary Intervention) randomized trial.

OBJECTIVES: The purpose of this study was to assess whether the early discontinuation of eptifibatide infusion in nonemergent percutaneous coronary intervention (PCI) is associated with a higher frequency of periprocedural ischemic myonecrosis. BACKGROUND: The recommended regimen for eptifibatide is a double bolus followed by an infusion for 18 h. It is not known whether the infusion can be shortened if the PCI is uncomplicated. METHODS: We enrolled 624 patients with stable angina, acute coronary syndrome, or recent ST-segment elevation myocardial infarction (>48 h) who underwent successful coronary stenting and received eptifibatide. Patients were randomly assigned to receive either an 18-h infusion or an abbreviated infusion of <2 h. The primary end point was the incidence of periprocedural myonecrosis defined as troponin-I elevation >0.26 microg/l. Secondary end points included death, myocardial infarction, urgent target vessel revascularization at 30 days, and in-hospital major bleeding using the REPLACE-2 (Randomized Evaluation in PCI Linking Angiomax to Reduced Clinical Events) trial criteria. RESULTS: The incidence of periprocedural myonecrosis was 30.1% in the <2-h group versus 28.3% in the 18-h group (mean difference: 1.8%; upper bound of 95% confidence interval: 7.8%; p < 0.012 for noninferiority). The 30-day incidence of myocardial infarction, death, and target vessel revascularization was similar in both groups (p = NS). Major bleeding was less frequent in the <2-h group (1.0% vs. 4.2%, p = 0.02). CONCLUSIONS: After uncomplicated PCI, eptifibatide infusion can be abbreviated safely to <2 h. It is not inferior to the standard 18-h infusion in preventing ischemic outcome, and it may be associated with less major bleeding. (Brief Infusion of Eptifibatide Following Percutaneous Coronary Intervention [BRIEF PCI]; NCT00111566).