Association of ischemic stroke to coronary artery disease using computed tomography coronary angiography

Transient ischemic attack and coronary artery disease: a two-sample Mendelian randomization analysis

Background

Although observational studies have shown that patients who experienced transient ischemic attacks (TIAs) had a higher risk of coronary artery disease (CAD), the causal relationship is ambiguous.

Methods

We conducted a two-sample Mendelian randomization (MR) study to analyze the causal relationship between TIA and CAD using data from the FinnGen genome-wide association study. Analysis was performed using the inverse-variance weighted (IVW) method. The robustness of the results was evaluated using MR-Egger regression, the weighted median, MR pleiotropy residual sum, and outlier (MR-PRESSO) and multivariable MR analysis.

Results

Results from IVW random-effect model showed that TIA was associated with an increased risk of coronary artery atherosclerosis (OR 1.17, 95% CI 1.06-1.28, P = 0.002), ischemic heart disease (OR 1.15, 95% CI 1.04-1.27, P = 0.007), and myocardial infarction (OR1.15, 95% CI 1.02-1.29, P = 0.025). In addition, heterogeneity and horizontal pleiotropy were observed in the ischemic heart disease results, while the sensitivity analysis revealed no evidence of horizontal pleiotropy in other outcomes.

Conclusions

This MR study demonstrated a potential causal relationship between TIA and CAD. Further research should be conducted to investigate the mechanism underlying the association.

Antithrombotic Therapy in Patients with Coronary Artery Disease and Prior Stroke

Patients with coronary artery disease (CAD) and prior cerebrovascular events (CVE) are frequently faced in clinical practice and present a high rate of both ischemic and bleeding events. For these reasons, the antithrombotic management is particularly challenging in this subgroup of patients. Recent trials suggest that, although a potent antiplatelet strategy is safe in the acute phases of myocardial ischemia for these patients, the risk of major bleeding complications, including intracranial hemorrhage, is extremely high when the antithrombotic therapy is prolonged for a long period of time. Therefore, especially in patients with chronic CAD and history of CVE, the antithrombotic management should be carefully balanced between ischemic and bleeding risks. The present review is aimed at critically evaluating the available evidence to help make these crucial clinical decisions regarding the better antithrombotic therapy to use in this high-risk subgroup of patients.

Comparison of Frequency of Ischemic Stroke in Patients With Versus Without Coronary Heart Disease and Without Atrial Fibrillation

Recent trials of antithrombotic therapy in patients with coronary artery disease (CAD) have demonstrated substantial reductions in ischemic stroke. Our aim was to examine ischemic stroke risk in patients with CAD and to identify those at highest risk. We examined ischemic stroke risk in patients without atrial fibrillation who underwent coronary angiography between 2004 and 2012. Patients were stratified according to presence or absence of CAD and further stratified by extent of CAD (0 vessel disease [VD], 1 VD, 2 VD, 3 VD, and diffuse VD). End points were composites of ischemic stroke, transient ischemic attack (TIA), and systemic embolism, as well as major adverse cardiovascular and cerebrovascular events (MACCE) defined as cardiac death, myocardial infarction, plus ischemic stroke, TIA, and systemic embolism. Adjusted incidence rate ratios (IRRs) were estimated. A total of 68,829 patients were included, 25,032 had 0 VD, 4,736 had diffuse VD, 18,471 had 1 VD, 10,588 had 2 VD, and 10,002 had 3 VD. Median follow-up was 4.0 years. CAD extent was associated with an increased risk of stroke, TIA, and systemic embolism (1 VD: adjusted IRR 1.02, 95% confidence interval [CI] 0.90 to 1.16; diffuse VD: adjusted IRR 1.22, 95% CI 1.02 to 1.47; 2 VD: adjusted IRR 1.28, 95% CI 1.12 to 1.45; 3 VD: adjusted IRR 1.37, 95% CI 1.20 to 1.55) compared with patients with 0 VD. Presence and extent of CAD were also associated with MACCE. In conclusion, CAD is associated with an increased risk of stroke, TIA, and systemic embolism and MACCE in patients without atrial fibrillation, and patients with coronary multi-VD are at highest risk and may be candidates for treatment strategies aiming at reducing ischemic stroke incidence.

Prognostic value of proximal left coronary artery flow velocity detected by transthoracic Doppler echocardiography

BACKGROUND

Lesions in the proximal left coronary artery (LCA) are associated with a poor prognosis compared with other lesional sites. Transthoracic Doppler echocardiography (TTDE) can help to detect proximal LCA flow, and an accelerated coronary flow velocity (CFV) indicates the presence of proximal LCA lesions. This study aimed to investigate the prognostic value of CFV in the proximal LCA measured by TTDE.

METHODS

We enrolled 1472 consecutive hemodynamically stable patients with known or suspected heart disease whose CFV was successfully detected using TTDE accompanied by routine echocardiography between 2008 and 2011. The primary outcome was cardiac death (acute myocardial infarction, heart failure, or sudden cardiac death) and patients were followed up over a median of 6.3 years.

RESULTS

Overall, 42 cardiac deaths (3%) were observed. An increased CFV was significantly associated with the outcome in several models based on potential confounders (age, rate pressure product, Framingham Risk Score, diabetes, coronary artery disease, hemoglobin, brain natriuretic peptide, estimated glomerular filtration rate, left ventricular mass, left ventricular ejection fraction, and E/e'). Using a receiver operating characteristic curve analysis, the optimal cut-off value for the CFV to the association of the outcome was 37 cm/s (area under the curve, 0.70; sensitivity, 82%; specificity, 62%). In sequential Cox proportional hazards models, the CFV added incremental prognostic information to the clinical and basic echocardiographic parameters (chi-squared: 110.7 to 146.6, P < 0.01).

CONCLUSIONS

An increased CFV in the proximal LCA was associated with cardiac death, incremental to the clinical and basic echocardiographic parameters.

Case Study: Ticagrelor in PLATO and Prasugrel in TRITON-TIMI 38 and TRILOGY-ACS Trials in Patients With Acute Coronary Syndromes

Cross-trial comparisons are typically inappropriate as there are often numerous differences in study designs, populations, end points, and loading doses of the study drugs. These differences are clearly reflected in the most recent updates to the European Society of Cardiology (ESC) non-ST elevation acute coronary syndrome (NSTE-ACS) and ST elevation myocardial infarction (STEMI) guidelines, which include recommendations for the use of the antiplatelet agents ticagrelor, prasugrel, and clopidogrel, based in part on results from the TRial to assess Improvement in Therapeutic Outcomes by optimizing platelet inhibitioN with prasugrel-Thrombolysis In Myocardial Infarction (TRITON-TIMI) 38, TaRgeted platelet Inhibition to cLarify the Optimal strateGy to medicallY manage Acute Coronary Syndromes (TRILOGY-ACS) and PLATelet inhibition and patient Outcomes (PLATO) trials. Here, we describe each of these trials in detail and explain the differences between them that make direct comparisons difficult. In conclusion, this information, along with the current guidelines and recommendations, will assist clinicians in deciding the most appropriate treatment pathway for their patients with NSTE-ACS and STEMI.

Quantifying the risk of heart disease following acute ischaemic stroke: a meta-analysis of over 50,000 participants

OBJECTIVE

Following an acute stroke, there is a high risk of recurrence. However, the leading cause of mortality following a stroke is due to coronary artery disease (CAD) and myocardial infarction (MI) but that risk has not been robustly quantified. We sought to reliably quantify the risk of ischaemic heart disease (IHD) in patients presenting with acute ischaemic stroke (AIS) in the absence of a known cardiac history.

SETTING

A meta-analysis study. PubMed, MEDLINE, EMBASE and Google Scholar were searched for potential studies up to October 2015. Included studies reported an acute cerebral ischaemic event and followed for CAD or MI within 1 year in patients without known IHD. Using arcsine transformed proportions for meta-analysis, studies were combined using a generic inverse variance random-effects model to calculate the pooled standardised mean difference and 95% CIs. These were interpreted as the percentage prevalence of CAD or incidence of MI following AIS.

RESULTS

17 studies with 4869 patients with AIS demonstrated a mean average of asymptomatic CAD in 52%. Anatomical methods of CAD detection revealed a prevalence of asymptomatic ≥ 50% coronary stenosis in 32% (95% CI 19% to 47%; p<0.00001). 8 studies with 47229 patients with ischaemic stroke revealed an overall risk of MI in the year following stroke of 3% (95% CI 1% to 5%; p<0.00001) despite the absence of any cardiac history.

CONCLUSIONS

One-third of patients with ischaemic stroke with no cardiac history have more than 50% coronary stenosis and 3% are at risk of developing MI within a year. Our findings provide a reliable quantitative measure of the risk of IHD following AIS in patients with no cardiac history.

Efficacy versus safety: the dilemma of using novel platelet inhibitors for the treatment of patients with ischemic stroke and coronary artery disease

Coronary and cerebrovascular atherothrombosis are the leading cause of mortality and morbidity worldwide. Novel antiplatelet agents have been established for the management of patients with clinically evident coronary atherothrombosis and are increasingly used in these patients. These agents, however, have shown limited efficacy in the prevention of cerebrovascular events and potential harm in patients with history of stroke or transient ischemic attack. Herein, the efficacy and safety of two established antiplatelet agents in patients with stroke – aspirin and clopidogrel – are reviewed with a focus on the use and challenges related to novel antiplatelet agents – prasugrel, ticagrelor, and vorapaxar – in patients at risk for and with a history of stroke or transient ischemic attack.

Assessment of major adverse cardiovascular events and ischemic stroke with coronary computed tomography angiography based upon angiographic diagnosis in a high-volume single center

BACKGROUND

Patient prognosis has been shown to directly correlate with the severity of coronary artery disease diagnosed by coronary computed tomography angiography (CCTA). Although the presence of coronary artery calcium has been associated with increased incidence of ischemic stroke, there are no data on the incidence of ischemic stroke based upon the severity of coronary artery disease by CCTA. Therefore, we sought to investigate the rate of major adverse cardiovascular events, including ischemic stroke, based upon the severity of coronary artery disease by CCTA over a 6-year period in a high-volume single military center.

METHODS

We performed a retrospective chart review of all CCTA studies to evaluate the incidence of all-cause mortality, non-fatal myocardial infarction, ischemic stroke, and late revascularization (>90 days following CCTA) from January 2005 until July 2012. We reviewed 1518 CCTA reports, dividing patients into groups with obstructive (≥50% stenosis), non-obstructive (<50% stenosis), and no coronary artery disease (no angiographic disease). Subsequent major adverse cardiovascular events data (incidence of all-cause mortality, ischemic stroke, non-fatal myocardial infarction, and late revascularization) were obtained.

RESULTS

Over a review period of 6 years with a resultant median follow-up period of 22 months (interquartile range = 13-34 months), the major adverse cardiovascular events rate was significantly higher with obstructive coronary artery disease compared to both non-obstructive coronary artery disease and no coronary artery disease (8.9% vs 0.7%, p < 0.001; 8.9% vs 1.6%, p < 0.001). The incidence of ischemic stroke alone was also significantly higher in those with obstructive coronary artery disease compared to those with no coronary artery disease (3.8% vs 0.4%, p < 0.001).

CONCLUSION

Being free of disease on CCTA was associated with excellent cardiovascular prognosis. Obstructive coronary artery disease was associated with a significantly increased incidence of ischemic stroke. There was also a direct correlation between the severity of coronary artery disease on CCTA and cardiovascular prognosis over the follow-up period of 24 months.

Role of CT angiography for detection of coronary atherosclerosis

As laparoscopic surgery is replacing open surgery, similarly computed tomography angiography is replacing invasive conventional cardiac angiography. In the last century, marvelous efforts in research have improved strategies for cure, diagnosis and prevention of fatal human diseases; however, coronary artery disease, as the most prevalent cause of mortality and morbidity in the world, has remained a great challenge. Due to advancements in technology and research, it has become more simple and robust to diagnose and treat coronary artery disease (CAD) with minimal or no intervention, promising to not only diagnosis at an early stage but potential prevention altogether. While most with obvious CAD can be diagnosed easily and quickly with ECG, those identified as 'low risk' require more extensive testing to diagnose or rule out CAD. For example in emergency departments, low-risk patients with chest pain are diagnosed solely depending on history, ECG and blood testing for biomarkers. This approach has resulted in either delayed or miss-diagnosis of Acute coronary syndrome. To prevent this, many emergency departments now use protocols for low-risk heart patients that include cardiac stress tests and/or CT heart imaging. This review provides an overview of the current literature on the value of Computed tomography angiography and discusses how prognostic information obtained with Computed tomography angiography can be used to further integrate the technique into clinical practice.

Association of cardiac events with coronary artery disease detected by 64-slice or greater coronary CT angiography: a systematic review and meta-analysis

BACKGROUND

The value of ≥64-slice coronary CT angiography (CCTA) to determine odds of cardiac death or non-fatal myocardial infarction (MI) needs further clarification.

METHODS

We performed a systematic review and meta-analysis using publications reporting events/severity of coronary artery disease (CAD) in patients with suspected CAD undergoing CCTA. Patients were divided into: no CAD, non-obstructive CAD (maximal stenosis <50%), and obstructive CAD (≥50% stenosis). Odds ratios with 95% confidence intervals were calculated using a fixed or random effects model. Heterogeneity was assessed using the I(2) index.

RESULTS

We included thirty-two studies comprising 41,960 patients with 363 all-cause deaths (15.0%), 114 cardiac deaths (4.7%), 342 MI (14.2%), 69 unstable angina (2.8%), and 1527 late revascularizations (63.2%) over 1.96 (SD 0.77) years of follow-up. Cardiac death or MI occurred in 0.04% without, 1.29% with non-obstructive, and 6.53% with obstructive CAD. OR for cardiac death or MI was: 14.92 (95% CI, 6.78 to 32.85) for obstructive CAD, 6.41 (95% CI, 2.44 to 16.84) for non-obstructive CAD versus no CAD, and 3.19 (95% CI, 2.29 to 4.45) for non-obstructive versus obstructive CAD and 6.56 (95% CI, 3.07 to 14.02) for no versus any CAD. Similar trends were noted for all-cause mortality and composite major adverse cardiovascular events.

CONCLUSIONS

Increasing CAD severity detected by CCTA is associated with cardiac death or MI, all-cause mortality, and composite major adverse cardiovascular events. Absence of CAD is associated with very low odds of major adverse events, but non-obstructive disease significantly increases odds of cardiac adverse events in this follow-up period.

Severity of coronary atherosclerosis and stroke incidence in 7-year follow-up

The purpose of this prospective study was to investigate the association between the severity of coronary atherosclerosis in angiography and the risk of stroke in symptomatic coronary artery disease (CAD) patients without atrial fibrillation or atrial flutter. Associations between stroke and coronary artery disease were examined in 1,183 subjects without a history of stroke and who were referred for diagnostic coronary angiography. Association between stoke and coronary artery disease was determined using the COX proportional hazard regression model. During the follow-up period (mean 6.7 years), 50 strokes occurred. In the group with strokes there was a higher prevalence of multi-vessel coronary artery disease (62 vs. 46 %, p < 0.01). In the COX proportional hazard regression model, multi-vessel CAD was significantly associated with the stroke hazard ratio (HR) of 1.8 (CI 1.03–3.43), determined from a 7-year period of observation. Symptomatic patients with multi-vessel CAD are thus at a high risk of stroke development.

Ticagrelor Versus Clopidogrel in Patients With Acute Coronary Syndromes and a History of Stroke or Transient Ischemic Attack

Background—

Patients with acute coronary syndromes and history of stroke or transient ischemic attack (TIA) have an increased rate of recurrent cardiac events and intracranial hemorrhages.

Methods and Results—

We evaluated treatment effects of ticagrelor versus clopidogrel in patients with acute coronary syndrome with and without a history of prior stroke or TIA in the PLATelet inhibition and patient Outcomes (PLATO) trial. Of the 18 624 randomized patients, 1152 (6.2%) had a history of stroke or TIA. Such patients had higher rates of myocardial infarction (11.5% versus 6.0%), death (10.5% versus 4.9%), stroke (3.4% versus 1.2%), and intracranial bleeding (0.8% versus 0.2%) than patients without prior stroke or TIA. Among patients with a history of stroke or TIA, the reduction of the primary composite outcome and total mortality at 1 year with ticagrelor versus clopidogrel was consistent with the overall trial results: 19.0% versus 20.8% (hazard ratio, 0.87; 95% confidence interval, 0.66–1.13; interaction P =0.84) and 7.9% versus 13.0% (hazard ratio, 0.62; 95% confidence interval, 0.42–0.91). The overall PLATO-defined bleeding rates were similar: 14.6% versus 14.9% (hazard ratio, 0.99; 95% confidence interval, 0.71–1.37), and intracranial bleeding occurred infrequently (4 versus 4 cases, respectively).

Conclusions—

Patients with acute coronary syndrome with a prior history of ischemic stroke or TIA had higher rates of clinical outcomes than patients without prior stroke or TIA. However, the efficacy and bleeding results of ticagrelor in these high-risk patients were consistent with the overall trial population, with a favorable clinical net benefit and associated impact on mortality.

Clinical Trial Registration—

URL: http://www.clinicatrials.gov . Unique identifier: NCT00391872.