Heart rate control with single administration of a long-acting β-blocker at bedtime before coronary computed tomography angiography

Noninvasive diagnostic modalities for the diagnosis of coronary artery disease: A guide for acute care NPs

ABSTRACT

Selecting noninvasive diagnostic tests for coronary artery disease can be a daunting task to acute care NPs. This article provides an overview of the pathophysiology of coronary artery disease, relevant noninvasive diagnostic imaging modalities, and an evidence-based approach to guide subsequent diagnostic and therapeutic interventions.

The Functional Severity Assessment of Coronary Stenosis Using Coronary Computed Tomography Angiography-Based Myocardial Mass at Risk and Minimal Lumen Diameter

Background

We investigated whether or not the addition of myocardial mass at risk (MMAR) to quantitative coronary angiography was useful for diagnosing functionally significant coronary stenosis in the daily practice.

Methods

We retrospectively enrolled 111 consecutive patients with 149 lesions who underwent clinically indicated coronary computed tomography angiography and subsequent elective coronary angiography with fractional flow reserve (FFR) measurement. MMAR was calculated using a workstation-based software program with ordinary thin slice images acquired for the computed tomography, and the minimal lumen diameter (MLD) and the diameter stenosis were measured with quantitative coronary angiography.

Results

The MLD and MMAR were significantly correlated with the FFR, and the MMAR-to-MLD ratio (MMAR/MLD) showed a good correlation. The area under the receiver operating characteristic curve (AUC) of MMAR/MLD for FFR ≤ 0.8 was 0.746, and the sensitivity, specificity, positive predictive value, and negative predictive value were 60%, 83%, 68%, and 77%, respectively, at a cut-off value of 29.5 ml/mm. The addition of MMAR/MLD to diameter stenosis thus made it possible to further discriminate lesions with FFR ≤ 0.8 (AUC = 0.750). For the proximal left coronary artery lesions, in particular, MMAR/MLD showed a better correlation with the FFR, and the AUC of MMAR/MLD for FFR ≤ 0.8 was 0.919 at a cut-off value of 31.7 ml/mm.

Conclusions

The index of MMAR/MLD correlated well with the physiological severity of coronary stenosis and showed good accuracy for detecting functional significance. The MMAR/MLD might be a useful parameter to consider when deciding the indication for revascularization.

Pilot study of bisoprolol 8mg transdermal patch at bedtime before coronary computed tomography angiography

BACKGROUND

Coronary computed tomography angiography (CCTA) is recommended for first-line evaluation of stable coronary artery disease, and there is a standard protocol to control heart rate (HR) in guidelines. However, time is required to decrease HR to the recommended ≤60 beats per minute (bpm). We investigated whether the bisoprolol 8mg transdermal patch at bedtime on the day before CCTA can achieve a target HR and simplify the CCTA process.

METHODS

We randomly assigned 63 patients with an HR of ≥70 bpm and systolic blood pressure ≥120mmHg to a standard protocol group (n=33) or a group (n=30) that applied a bisoprolol 8mg transdermal patch (Bis) at bedtime on the day before CCTA evaluation. The primary endpoint was a change in HR between enrollment in the study and the time of CCTA evaluation. The secondary endpoints were elapsed time from arrival at the CCTA suite to starting CCTA image acquisition, and the rates of oral metoprolol and intravenous landiolol administration (UMIN00035246).

RESULTS

Baseline characteristics did not significantly differ between two groups. HR was significantly lower upon arrival at the CCTA suite in Bis, than standard protocol group (67.5±7.8 bpm vs. 75.0±10.6 bpm; p=0.00002), and the amount of elapsed time from arrival to the start of CCTA evaluation was also significantly decreased in Bis group (76.9±34.9min vs. 94.8±29.2min; p=0.0356). Rates of oral metoprolol and intravenous landiolol administration did not significantly differ between two groups (63.3% vs. 83.3%, p=0.143 and 36.7% vs. 60.0%, p=0.12, respectively).

CONCLUSIONS

The bisoprolol 8mg transdermal patch lowered HR and decreased the amount of time needed for CCTA, thus streamlining the evaluation process.

Salvianolic acid B induced upregulation of miR-30a protects cardiac myocytes from ischemia/reperfusion injury

BACKGROUND

MicroRNAs (miRNAs) are a novel class of powerful, endogenous regulators of gene expression. This study was designed to ascertain if miR-30a is involved in the cardioprotective actions of salvianolic acid B (Sal B) against myocardial ischemia-reperfusion (I-R) injury through suppression of autophagy.

METHODS

Murine myocardial cells that had undergone primary culture were induced by I-R and incubated with Sal B (25, 50, 100 μM) in the presence of a miR-30a mimic or miR-30a inhibitor. Expression of miR-30a, beclin-1, LC3-II and p-Akt protein, cell viability, and lactic acid dehydrogenase (LDH) release were assessed.

RESULTS

miR-30a expression was down-regulated remarkably in I-R cells, and this suppression could be reversed by Sal B in a dose-dependent manner. Sal B repressed autophagy in I-R myocardial cells. Sal B improved cell viability and reduced the rate of LDH leakage, which suggested that autophagy suppression was beneficial for cell survival. Knockdown of miR-30a with a miR-30a inhibitor could reverse the anti-autophagy effect of Sal B against I-R injury. Furthermore, we confirmed that Sal B has a protective role in miR-30a-mediated autophagy through the PI3K/Akt signaling pathway, which was abrogated by the PI3K inhibitor LY294002.

CONCLUSIONS

These data suggest that miR-30a is involved in Sal B-mediated cardioprotection against I-R injury through the PI3K/Akt signaling pathway.

Incremental value of B-type natriuretic peptide for detection and risk reclassification of obstructive coronary artery disease on computed tomography angiography

BACKGROUND

B-type natriuretic peptide (BNP) is well known to increase as a result of left ventricular systolic dysfunction and is a useful diagnostic marker for heart failure. The purpose of this study was to assess the incremental value of BNP for predicting obstructive coronary artery disease (CAD) on computed tomography angiography (CTA) in patients with suspected CAD.

METHODS

This was an observational analysis of patients with stable CAD undergoing CTA in our institution between April 2008 and June 2014. Consecutive 947 patients with suspected CAD who underwent 64-slice CTA were enrolled. Obstructive CAD was defined as more than 50% luminal narrowing. We divided the patients into 2 groups according to median BNP value (20.3pg/ml). Duke clinical score for obstructive CAD was calculated for each patient.

RESULTS

Obstructive CAD was found in 273 (28.0%) patients. Median follow-up period was 37 months (interquartile range 21-55 months). Kaplan-Meier curves showed that BNP above median was significantly associated with major adverse cardiac events (p=0.001). In multivariable logistic analysis, patients with BNP above median were associated with the presence of obstructive CAD, as compared with BNP below median [odds ratio, 2.55; 95% confidence interval (CI), 1.79-3.63; p<0.001]. Analyzing the incremental value of the Duke clinical score and BNP, the predictive value of the Duke clinical score [area under the curve (AUC), 0.714] could be increased by BNP (AUC 0.745 for the combined model; p<0.001). Addition of BNP to a model containing the Duke clinical score resulted in net reclassification improvement index of 0.14 (95% CI: 0.053-0.205, p<0.001).

CONCLUSIONS

BNP might provide an incremental improvement in the detection of obstructive CAD on CTA when combined with a conventional cardiovascular risk score.

Coronary Artery Disease Screening With Carotid Ultrasound Examination by a Primary Care Physician

Background

In this study, we investigated the feasibility of primary care physicians using carotid ultrasound to perform coronary artery disease screening in asymptomatic patients with multiple coronary risk factors.

Methods

We retrospectively collected the data of 135 consecutive asymptomatic patients (mean age: 68.5 ± 8.4 years; male, 75%) who were referred to our institution due to abnormal findings on a carotid ultrasound performed by a primary care physician and who underwent coronary computed tomography angiography.

Results

The mean number of risk factors was 4.1 ± 1.2 and the mean intima-media thickness was 2.00 ± 0.63 mm. Mild (≤ 50%), moderate (51-75%), and severe (> 76%) coronary stenosis was observed in 54 (40%), 27 (20%), and 25 patients (19%), respectively, while no plaque was found in 24 patients (18%), and five patients (4%) could not be evaluated due to calcification. Consequently, coronary angiography was performed in 56 (41%) patients and coronary intervention was required in 31 patients (23%). A multivariate logistic regression analysis demonstrated that the ratio of low-density lipoprotein cholesterol levels to high-density lipoprotein cholesterol levels, the use of calcium channel blockers and the value of the diastolic blood pressure were related to > 50% coronary stenosis.

Conclusions

The use of carotid ultrasound in the coronary artery disease screening by primary care physicians resulted in a high prevalence of coronary artery disease and high probabilities of coronary angiography and revascularization, and thus it is considered to be a useful and feasible strategy for the screening of asymptomatic patients.

Shuangshen Ningxin Capsule, a Traditional Chinese Medicinal Preparation, Alleviates Myocardial Ischemia through Autophagy Regulation

Shuangshen Ningxin capsule (SSNX), a modern Chinese formula, has been used to treat cardiovascular diseases in Eastern Asia. Our study focuses on the autophagy regulation of SSNX against coronary artery injuries. Myocardial infarction model was established in Chinese miniswines (CMS) by coronary artery balloon injury. SSNX was administered to the CMS for 8 weeks with 4 mg/kg or 16 mg/kg. Myocardial cells were incubated with 20% SSNX medicated serum for 2 hours. Assays were performed to detect the effects of SSNX on (i) coronary artery diameter by angiography, (ii) hemodynamics by noninvasive hemodynamic monitoring system, (iii) plaque burden and plaque volume by intravenous ultrasound (iv) coronary artery histology by H&E staining, (v) autophagosome by transmission electron microscopy, (vi) lactate dehydrogenase (LDH) leakage, and (vii) Beclin-1 and LC3-I/II expressions by Western blot. The results showed that CMS treated with SSNX exhibited the correction for the disturbed cardiac hemodynamics, increase of coronary artery diameter, reduction of high plaque burden and plaque volume, and decrease of LDH. The inhibitory effect of SSNX on CMS autophagy was demonstrated by the reduction of autophagosome and the downregulation of beclin-1 and LC3-I/II. SSNX may protect coronary artery and increase the stability of plaque through the suppression of myocardial cellular autophagy, which suggests the potentially therapeutic effect of SSNX on ischemic cardiovascular disease.