Percutaneous Coronary Intervention

The Alberta Provincial Project for Outcome Assessment in Coronary Heart Disease (APPROACH) is a province-wide inception cohort of all adult Alberta residents undergoing cardiac catheterization for ischemic heart disease [10 (link)]. APPROACH was initiated to study provincial outcomes of care and facilitate quality assurance/quality improvement for patients with coronary artery disease in Alberta. The APPROACH database contains detailed clinical information on adult patients with known or suspected coronary artery disease (CAD) who undergo invasive cardiac procedures. Patients in APPROACH are followed longitudinally after cardiac catheterization, thus allowing for assessment of subsequent procedure use (i.e. percutaneous coronary intervention [PCI] or coronary artery bypass graft surgery [CABG]), as well as outcomes such as mortality and quality of life. Data collection is ongoing, and as is typical in prospective data registries, there are occasionally data fields that are not completed in the data collection process.

To enhance interpretation of all presented graphical and numerical summaries we used three worked examples of NMAs. The first example compares 14 antimanic drugs for acute mania [14] (link). The network included 47 studies reporting on efficacy (measured as the number of responders out of total randomized) and 64 studies reporting on acceptability (measured as the number of dropouts out of total randomized). The second example is a network of 62 studies that evaluate the effectiveness of four different percutaneous coronary interventions for non-acute coronary artery disease [15] (link). The third example is a network of 27 studies forming a star-shaped network (i.e. all active treatments are compared only with placebo) that evaluated the effectiveness of six biologic agents for rheumatoid arthritis [16] (link). The outcome in this network was benefit from treatment defined as a 50% improvement in patient- and physician-reported criteria of the American College of Rheumatology (ACR50). The datasets and the STATA routines can be found online in www.mtm.uoi.gr and more detail is provided in the Appendix S1. To be able to carry out the analysis described below, version 3.01 (or later) of the command metan, version 2.6.1 (or later) of metareg and version 2.5.5 (or later) of mvmeta are required.

The study population was selected from the Korean Acute Myocardial Infarction Registry-National Institutes of Health (KAMIR-NIH) [10 (link)]. KAMIR-NIH is a nation-wide, prospective, multicenter, web-based observational cohort study aiming to develop a prognostic and surveillance index for patients with AMI. Patients who were hospitalized primarily for AMI and signed informed consents were consecutively enrolled from November 2011 to October 2015. This study was conducted according to the ethical guidelines of the Declaration of Helsinki. The study protocol was approved by the ethics committee at Chonnam National University Hospital, Republic of Korea (IRB No. CNUH-2011-172) and the institutional review boards of all participating hospitals approved the study protocol. Written informed consents were obtained from participating patients or legal representative. Data were collected by the attending physician with the assistance of a trained clinical research coordinator, via a web-based case report form in the clinical data management system of the Korea NIH. Patients, who died during index hospitalization, did not have hypertension, were prescribed neither ACEI nor ARB, or both ACEI and ARB at discharge, did not undergo echocardiographic study, and had incomplete clinical data, were excluded.
AMI was diagnosed when there was an evidence of myocardial necrosis (a rise and/or fall in cardiac biomarker, preferably cardiac troponin), and at least one of the following: (1) symptoms of ischemia, (2) new or presumed new significant ST-segment-T wave changes or a new left bundle branch block, (3) a development of pathologic Q waves in the electrocardiogram, (4) an imaging evidence of the new loss of viable myocardium or new regional wall motion abnormality, and (5) the identification of an intracoronary thrombus by angiography [11 (link)]. Hypertension was defined as values ≥140 mmHg of systolic BP (SBP) and/or ≥90 mmHg of diastolic BP (DBP) during the initial hospitalization [12 (link), 13 (link)]. Patients with a history of hypertension or antihypertensive treatment on the interview were also considered to have hypertension. Coronary reperfusion included reperfusion by percutaneous coronary intervention (PCI), thrombolysis, or coronary artery bypass graft (CABG), MI with non-obstructed coronary arteries (MINOCA) [3 (link)], and myocardial bridge. LV systolic function was evaluated by the echocardiographic study during the initial hospitalization.

All patients included underwent review of medical records for evidence of oeCAD by two study investigators (R.H., N.M.F.), including symptom history, cardiovascular risk factors, healthcare encounters such as ambulatory clinic visits, Emergency Department visits and hospitalizations, and cardiac investigation findings such as electrocardiogram (ECG), cardiac biomarker (troponin and N-terminal pro-B-type natriuretic peptide, NTproBNP), ECG stress test, stress imaging, coronary computed tomography angiography (CCTA), invasive coronary angiography, history of acute coronary syndrome (ACS) or myocardial infarction (MI), and/or coronary artery revascularization. The clinical indication for oeCAD evaluation, in addition to the temporal relation with ATTR-CM diagnosis (occurring before, after, or simultaneous with) was also collected.
As patients with ATTR-CM often have clinical characteristics and/or non-invasive investigation result findings that resemble oeCAD (such as chest pain, chronically elevated troponin levels, and anterior Q-waves on ECG), a strict definition of oeCAD was used for this analysis. A diagnosis of CAD required ≥ 1 of the following criteria: (1) prior history of coronary artery revascularization by either percutaneous coronary intervention (PCI) and/or coronary artery bypass grafting (CABG), (2) obstructive epicardial coronary artery stenosis of ≥ 70% by CCTA or invasive coronary angiography, or ≥ 50% of the left main coronary artery [11 (link)]. This strict criteria was selected in order to definitively confirm the presence of obstructive epicardial coronary artery disease lesions in ATTR-CM patients, and to discriminate the presence oeCAD from patients who may have microvascular coronary artery disease or findings on non-invasive evaluation (such as ECG or echocardiography) that are secondary to myocardial amyloid fibril infiltration but resemble oeCAD. Among patients with a prior history of ACS/MI, all had subsequent confirmatory invasive coronary angiography.

One-hundred and eighteen patients who were admitted to a tertiary cardiac care hospital of SUMS (Ghalb-Al-Zahra hospital) with the diagnosis of CAD were recruited into the study. fifty-two subjects with normal coronary angiography or non-significant CAD (< 50% coronary stenosis) who visited a tertiary care clinic for more CAD evaluation were enrolled in the study as the control group. All of the protocols conformed to the ethical guidelines of the Helsinki Declaration.
Inclusion criteria for the CAD group were as follows: Ages between 18 and 80 years old, confirmed diagnosis of CAD (> 50% luminal stenosis in at least one major coronary artery in angiography) and successful percutaneous coronary intervention (PCI). Exclusion criteria for both groups include severe liver disease, active malignancies, chronic inflammatory disease, history of surgery, or severe trauma in the last month, and administration of immunosuppressive drugs.
All demographic and clinical data were obtained from patients’ histories and medical records. Participants who actively smoked cigarettes were considered as smokers. No documented history of CAD duration before hospitalization was available.