Safety, Efficacy and Indications of β-Blockers to Reduce Heart Rate prior to Coronary CT Angiography-An Overview.

For selected indications, coronary computed tomographic (CT) angiography is an established clinical technology for evaluation in patients suspected of having or known to have coronary artery disease. In coronary CT angiography, image quality is highly dependent on heart rate, with heart rate reduction to less than 60 beats per minute being important for both image quality and radiation dose reduction, especially when single-source CT scanners are used. â-Blockers are the first-line option for short-term reduction of heart rate prior to coronary CT angiography. In recent years, multiple âblocker administration protocols with oral and/or intravenous application have been proposed. This review article provides an overview of the indications, efficacy, and safety of â-blockade protocols prior to coronary CT angiography with respect to different scanner techniques. Moreover, implications for radiation exposure and left ventricular function analysis are discussed.

Myocardial Perfusion Imaging (MPI), An Overview.

The clinical utility of radiotracer study of heart in nuclear cardiology must always be considered in the of context of other cardiac diagnostic procedures, including ECG, Echo, ETT,CAG and cardiac enzymes or serum cardiac protein. So one should not be a hop cardiologist. Two modalities in Nuclear Cardiology: 1).Radionuclide Angiography (RNA) or Radionuclide Ventriculography. 2).Myocardial Perfusion Imaging (MPI). Radionuclide Angiography (RNA) or Radionuclide Ventriculography: This procedure is designed to provide measurement of LVEF in patient of coronary artery disease, valvular heart disease or cardiomyopathy. In our setting we determine EF from MPI, so Radionuclide Angiography routinely not do in many centre of world including NICVD, Dhaka. Myocardial Perfusion Imaging (MPI): MPI, more specifically myocardial perfusion single photon emission computed tomography (SPECT) is a nice tool for the noninvasive assessment of myocardial perfusion, ejection fraction, wall motion, and wall thickness. Why not perform cardiac catheterization and coronary angiography in all patients suspected of having coronary artery diseases? The contrast coronary angiogram displays the anatomic extent of epicardial coronary artery disease, the severity of luminal narrowing, and the number of diseased vessels. Stress radionuclide myocardial perfusion imaging, on the other hand, displays the downstream functional consequences of epicardial coronary artery disease in the myocardium. It also may visualize the regional effects of micro vascular endothelial dysfunction and impairment of regional coronary flow reserve. Application of MPI: The diagnosis of coronary artery disease remain common application of MPI ,but it is increasingly being used for the diagnosis of acute MI, risk stratification after infarction, and assessment of viable myocardium versus scar in patients in chronic coronary artery disease.

Non-invasive Diagnosis in Clinically Suspected ASD Secundum.

Background: The non-invasive tests like X-ray, ECG and Echocardiography are viewed as an extension of clinical art in cardiology and have become an integral part of history taking, physical examination and other diagnostic method.Atrial Septal Defect (ASD) of secundum type is defined as a through and through communication at atrial level. Previously the diagnosis and decision of surgery for ASD, mandatorily advocate cardiac catherization.Now cardiologist and cardiac surgeon very hardly asked for cardiac catheterization. Non-invasive diagnosis with the help of ECG, X-ray and Echo is sufficient for its diagnosis and treatment for surgery. In Bangladesh there is no study upon it. Considering this ground the study is perform on Bangladeshi patients. Methods: Forty six consecutive patients with clinical (auscultatory and electrocardiographic) signs of uncomplicated atrial septal defect of secundum type were examined by chest x-ray, ECG and echocardiography, before right heart catheterisation. Result: Thirty four (74%) had ASD, four patients (9%) had insignificant pulmonary stenosis, and eight subjects (17%) were normal. No false positive diagnosis of atrial septal defect was made by chest x-ray examination, whereas increased vascular markings were incorrectly interpreted as pulmonary congestion in one case. Eight patients had x-ray films showing questionable signs of left-to-right shunt. Twelve of 30 patients with a large left-to-right shunt were correctly selected for surgery based on radiological findings. Conclusion: Analysis of non invasive diagnosis and management of ASD secundum conform the usually described pattern in western literature.

Diagnostic and Therapeutic Value of Cardiac Scan: First Experience of Utility and Prosfect of MPI in Bangladesh.

Background: Cardiac Scan (MP-SPECT) is a widely utilized noninvasive imaging modality for diagnosis, prognosis, and risk stratification of coronary artery disease. In Bangladesh it is a recently introduced test and there is no study upon it. Considering this ground the study is perform on Bangladeshi patients. Methods: 100 referral patients underwent MPI for evaluation of perfusion status of myocardium. The patients either of suspected IHD or diagnosed case of IHD were referred from different cardiology unit or surgery unit of NICVD. Technetium 99m (99"Tc) isotopes and tetrofosmin used in the same day stress and rest protocol. Result: The commonest findings observed in this present analysis were the early age group patients mostly of female having DCM, but the later age group of patients are of both male and female having Angina Pectoris, OMI and ICM. The referral patients by cardiologists or cardiac surgeons are mostly limited to the pre therapeutic evaluation rather than diagnostic indication. The most common indication is the evaluation of myocardial viability and aim of subsequent treatment. Conclusion: Analysis of perfusion status, decision of subsequent treatment either by medicine or CABG, conform the usually described pattern in western literature.