Despite recent advances in clinical imaging, echocardiography remains as the most accessible and reliable noninvasive. Since knowledge of left ventricular systolic function remains so critically important in determining prognosis; every effort should be made to prevent subjective estimations. The advent of strain imaging echocardiography now offers a readily available and portable imaging tool that not only offers an objective characterization of myocardial dynamics; but also allows for early detection of subclinical left ventricular dysfunction. This review outlines the basic concepts of strain imaging to better understand the mechanism of myocardial function as well their applicability in the least common cardiac diagnosis among current clinical practice.

Background: Previous reports have shown inadequate response to dual antiplatelet therapy (DAPT) with aspirin and clopidogrel in 5-30% of patients undergoing percutaneous coronary interventions (PCI), due mostly to clopidogrel resistance. This prevalence increases up to 66% in patients undergoing neurointerventional procedures. However, clinical significance of CYP2C19 genotypes in neurointerventional procedures or carotid artery stenting (CAS) is unknown. Objective: The purpose of this review is to update our current knowledge and understanding of the pharmacogenetic basis for poor clopidogrel responsiveness in patients undergoing CAS and endovascular interventions as well as to explore usefulness of genotyping to reduce the rate of procedure-related thrombosis that results in ischemic complications. Method: A literature search for pharmacogenetic studies in cerebral endovascular interventions and CAS was conducted on three databases using a list of the most relevant pharmacogenetic biomarkers. Results: The review included 7 papers involving 3 genetic polymorphisms on CYP2C19 and 442 subjects. Patients harboring at least one loss-of-function CYP2C19 polymorphism (e.g., CYP2C19*2 and *3) are at an increased risk of thromboembolic complications such as stent thrombosis following neurointerventional procedures. Notably, patients who carry the gain-of-function CYP2C19*17 allele may have increased risk of ischemic events following endovascular treatment, independent of clopidogrel responsiveness. Conclusion: Studies assessing the influence of CYP2C19 polymorphisms on high on-treatment platelet reactivity in CAS and cerebrovascular disease patients are still limited and need further validation in large multicenter studies. This review covers an important topic in the field of antiplatelet therapy for cerebral endovascular procedures and CAS.

Introduction: High on-treatment platelet reactivity (HTPR) to clopidogrel imparts an increased risk for ischemic events in adults with coronary artery disease. Platelet reactivity varies with ethnicity and is influenced by both clinical and genetic variables; however, no clopidogrel pharmacogenetic studies with Puerto Rican patients have been reported. Therefore, we sought to identify clinical and genetic determinants of on-treatment platelet reactivity in a cohort of Puerto Rican patients with cardiovascular disease. Methods: We performed a retrospective study of 111 patients on 75 mg/day maintenance dose of clopidogrel. Patients were allocated into 2 groups: Group I, without HTPR; and Group II, with HTPR. Platelet function was measured ex vivo using the VerifyNow® P2Y12 assay and HTPR was defined as P2Y12 reaction units (PRU) ≥230. Genotyping testing was performed using Taqman® Genotyping Assays. Results: The mean PRU across the cohort was 203±61 PRU (range 8–324), and 42 (38%) patients had HTPR. Multiple logistic regression showed that 27% of the total variation in PRU was explained by a history of diabetes mellitus, hematocrit, CYP2C19*2, and PON1 p.Q192R. Body mass index (odds ratio [OR]=1.15; 95% CI: 1.03–1.27), diabetes mellitus (OR=3.46; 95% CI: 1.05–11.43), hematocrit (OR=0.75; 95% CI: 0.65–0.87), and CYP2C19*2 (OR=4.44; 95% CI: 1.21–16.20) were the only independent predictors of HTPR. Conclusion: Moreover, we propose a predictive model to determine PRU values as measured by VerifyNow P2Y12 assay for the Puerto Rican Hispanic population. This model has the potential to identify Hispanic patients at higher risk for adverse events on clopidogrel.