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Permanent cardiac pacing in Malaysia. An update

Saw HS, Chong KT, Singham AM

Ann Acad Med Singap, 1981 Oct;10(4 Suppl):93-8.
PMID: 7344608

Updated data on permanent cardiac pacing in Malaysia is presented. Over the past 3 1/2 years (1976-1980), 75 patients underwent insertion of pacemakers giving an annual incidence of about 20 cases as compared with a total of 21 cases in the previous 8 years (1968-1977). Many of the features reported in an earlier paper in 1977 viz mode of presentation, age and sex distribution and indications for pacing remain unchanged. Over this period only 4 patients required lead replacement. Since concentrating mainly on the use of epicardial leads implanted via a subxiphoid approach, complications have been remarkably low. The problem of availability of pacemakers has been averted. Cost remains a major consideration when recommending one pacemaker in preference over another. The details concerning clinical features, indications for pacing, complications and other problems encountered in the management of these patients are discussed.

Matched MeSH terms: Heart Diseases/mortality; Heart Diseases/epidemiology; Heart Diseases/therapy*
Fulltext Indications of temporary transvenous pacing

Chin K, Singham KT, Masduki A

Med J Malaysia, 1984 Jun;39(2):139-42.
PMID: 6513853

A retrospective study of the indications for temporary transvenous pacing in the University Hospital, Kuala Lumpur, from 1971 to 1979 is reviewed. There were 111 patients. The main indications for temporary transvenous pacing were, namely,complete heart block (57%), sick sinus syndrome (24%), Mobitz type 11 block (5%) and bifascicularblock (3%).

Matched MeSH terms: Heart Block/therapy*; Heart Failure/therapy*
The use of BLRP model for disaggregating daily rainfall affected by monsoon in Peninsular Malaysia

Zulkifli Yusop, Harisaweni, Fadhilah Yusof

Sains Malaysiana, 2016;45:87-97.

Rainfall intensity is the main input variable in various hydrological analysis and modeling. Unfortunately, the quality of rainfall data is often poor and reliable data records are available at coarse intervals such as yearly, monthly and daily. Short interval rainfall records are scarce because of high cost and low reliability of the measurement and the monitoring systems. One way to solve this problem is by disaggregating the coarse intervals to generate the short one using the stochastic method. This paper describes the use of the Bartlett Lewis Rectangular Pulse (BLRP) model. The method was used to disaggregate 10 years of daily data for generating hourly data from 5 rainfall stations in Kelantan as representative area affected by monsoon period and 5 rainfall stations in Damansara affected by inter-monsoon period. The models were evaluated on their ability to reproduce standard and extreme rainfall model statistics derived from the historical record over disaggregation simulation results. The disaggregation of daily to hourly rainfall produced monthly and daily means and variances that closely match the historical records. However, for the disaggregation of daily to hourly rainfall, the standard deviation values are lower than the historical ones. Despite the marked differences in the standard deviation, both data series exhibit similar patterns and the model adequately preserve the trends of all the properties used in evaluating its performances.

Matched MeSH terms: Heart Rate
Fulltext Acute Metabolic Changes with Thigh-Positioned Wearable Resistances during Submaximal Running in Endurance-Trained Runners

Field AP, Gill N, Macadam P, Plews D

Sports (Basel), 2019 Aug 01;7(8).
PMID: 31375020 DOI: 10.3390/sports7080187

The aim of this study was to determine the acute metabolic effects of different magnitudes of wearable resistance (WR) attached to the thigh during submaximal running. Twenty endurance-trained runners (40.8 ± 8.2 years, 1.77 ± 0.7 m, 75.4 ± 9.2 kg) completed six submaximal eight-minute running trials unloaded and with WRs of 1%, 2%, 3%, 4% and 5% body mass (BM), in a random order. The use of a WR resulted in a 1.6 ± 0.6% increase in oxygen consumption (VO2) for every 1% BM of additional load. Inferential based analysis found that the loading of ≥3% BM was needed to elicit any substantial responses in VO2, with an increase that was likely to be moderate in scale (effect size (ES) ± 90% confidential interval (CI): 0.24 ± 0.07). Using heart rate data, a training load score was extrapolated to quantify the amount of internal stress. For every 1% BM of WR, there is an extra 0.17 ± 0.06 estimated increase in training load. A WR ≥3% of BM was needed to elicit substantial responses in lactate production, with an increase which was very likely to be large in scale (ES ± 90% CI: 0.41 ± 0.18). A thigh-positioned WR provides a running-specific overload with loads ≥3% BM, resulting in substantial changes in metabolic responses.

Matched MeSH terms: Heart Rate
Fulltext Atrioventricular Synchronous Pacing Using a Leadless Ventricular Pacemaker: Results From the MARVEL 2 Study

Steinwender C, Khelae SK, Garweg C, Chan JYS, Ritter P, Johansen JB, et al.

JACC Clin Electrophysiol, 2020 01;6(1):94-106.
PMID: 31709982 DOI: 10.1016/j.jacep.2019.10.017

OBJECTIVES: This study reports on the performance of a leadless ventricular pacemaker with automated, enhanced accelerometer-based algorithms that provide atrioventricular (AV) synchronous pacing.
BACKGROUND: Despite many advantages, leadless pacemakers are currently only capable of single-chamber ventricular pacing.
METHODS: The prospective MARVEL 2 (Micra Atrial tRacking using a Ventricular accELerometer 2) study assessed the performance of an automated, enhanced accelerometer-based algorithm downloaded to the Micra leadless pacemaker for up to 5 h in patients with AV block. The primary efficacy objective was to demonstrate the superiority of the algorithm to provide AV synchronous (VDD) pacing versus VVI-50 pacing in patients with sinus rhythm and complete AV block. The primary safety objective was to demonstrate that the algorithm did not result in pauses or heart rates of >100 beats/min.
RESULTS: Overall, 75 patients from 12 centers were enrolled; an accelerometer-based algorithm was downloaded to their leadless pacemakers. Among the 40 patients with sinus rhythm and complete AV block included in the primary efficacy objective analysis, the proportion of patients with ≥70% AV synchrony at rest was significantly greater with VDD pacing than with VVI pacing (95% vs. 0%; p

Matched MeSH terms: Heart Atria/physiopathology*; Heart Ventricles/physiopathology*
The treatment of acute cardiac beri-beri or 'shoshin' with massive doses of vitamin B1

Hawes RB, Monteiro ES, Smith CE

Journal of the Malaya Branch of the British Medical Association, 1937;1:87-96.

Matched MeSH terms: Heart Diseases
Tetralogy of Fallot correction with transannular patch reconstruction in a patient with an anomalous right coronary artery and an unusual course of the right ventricular branch

Gonzalez SA, Sivalingam S

Indian J Thorac Cardiovasc Surg, 2021 May;37(3):329-333.
PMID: 33967425 DOI: 10.1007/s12055-020-01074-0

Anomalous coronary arteries occur in as many as 12% of patients with tetralogy of Fallot (TOF). In patients with this condition, pulmonary hypoplasia can be prohibitive in performing a valve-sparing repair, subsequently resulting in various techniques to preserve the anomalous coronary artery. The management strategy is often complex in such a situation. We report on a case of TOF with an anomalous right coronary artery crossing the right ventricular outflow tract, with an unusual course of the right ventricular (RV) branch, which precluded placement of a valved conduit. In this case, we performed a successful repair with mobilization of the anomalous coronary artery and reconstruction of the right ventricular outflow tract with a limited transannular patch.

Matched MeSH terms: Heart Ventricles
Fulltext Clinical Practice Guidelines: Management on Heart Failure, 4th Edition

ISBN: 978-967-11794-4-4

Citation: Clinical Practice Guidelines: Management on Heart Failure, 4th Edition. Putrajaya: Ministry of Health, Malaysia; 2019

Older versions: Third Edition (2014); Second Edition (2007); First Edition (2000)
Keywords: CPG

Matched MeSH terms: Heart Failure
Posterior Spinal Fusion in a Scoliotic Patient With Congenital Heart Block Treated With Pacemaker: An Intraoperative Technical Difficulty

Wong TS, Abu Bakar J, Chee KH, Hasan MS, Chung WH, Chiu CK, et al.

Spine (Phila Pa 1976), 2019 02 15;44(4):E252-E257.
PMID: 30086081 DOI: 10.1097/BRS.0000000000002828

STUDY DESIGN: Case report.
OBJECTIVE: To describe the technical difficulties on performing posterior spinal fusion (PSF) on a pacemaker-dependent patient with complete congenital heart block and right thoracic scoliosis.
SUMMARY OF BACKGROUND DATA: Congenital complete heart block requires pacemaker implantation at birth through thoracotomy, which can result in scoliosis. Corrective surgery in this patient was challenging. Height gain after corrective surgery may potentially cause lead dislodgement. The usage of monopolar electrocautery may interfere with the function of the implanted cardiac device.
METHODS: A 17-year-old boy was referred to our institution for the treatment of right thoracic scoliosis of 70°. He had underlying complete congenital heart block secondary to maternal systemic lupus erythematosus. Pacemaker was implanted through thoracotomy since birth and later changed for four times. PSF was performed by two attending surgeons with a temporary pacing inserted before the surgery. The monopolar electrocautery device was used throughout the surgery.
RESULTS: The PSF was successfully performed without any technical issues and complications. Postoperatively, his permanent pacemaker was functioning normally. Three days later, he was recovering well and was discharged home from hospital.
CONCLUSION: This case indicates that PSF can be performed successfully with thoughtful anticipation of technical difficulties on a pacemaker-dependent patient with underlying congenital heart block.
LEVEL OF EVIDENCE: 5.

Matched MeSH terms: Heart Block/complications; Heart Block/congenital*; Heart Block/therapy
Fulltext Behavior of AV synchrony pacing mode in a leadless pacemaker during variable AV conduction and arrhythmias

Garweg C, Khelae SK, Chan JYS, Chinitz L, Ritter P, Johansen JB, et al.

J Cardiovasc Electrophysiol, 2021 07;32(7):1947-1957.
PMID: 33928713 DOI: 10.1111/jce.15061

INTRODUCTION: MARVEL 2 assessed the efficacy of mechanical atrial sensing by a ventricular leadless pacemaker, enabling a VDD pacing mode. The behavior of the enhanced MARVEL 2 algorithm during variable atrio-ventricular conduction (AVC) and/or arrhythmias has not been characterized and is the focus of this study.
METHODS: Of the 75 patients enrolled in the MARVEL 2 study, 73 had a rhythm assessment and were included in the analysis. The enhanced MARVEL 2 algorithm included a mode-switching algorithm that automatically switches between VDD and ventricular only antibradycardia pacing (VVI)-40 depending upon AVC status.
RESULTS: Forty-two patients (58%) had persistent third degree AV block (AVB), 18 (25%) had 1:1 AVC, 5 (7%) had variable AVC status, and 8 (11%) had atrial arrhythmias. Among the 42 patients with persistent third degree AVB, the median ventricular pacing (VP) percentage was 99.9% compared to 0.2% among those with 1:1 AVC. As AVC status changed, the algorithm switched to VDD when the ventricular rate dropped less than 40 bpm. During atrial fibrillation (AF) with ventricular response greater than 40 bpm, VVI-40 mode was maintained. No pauses longer than 1500 ms were observed. Frequent ventricular premature beats reduced the percentage of AV synchrony. During AF, the atrial signal was of low amplitude and there was infrequent sensing.
CONCLUSION: The mode switching algorithm reduced VP in patients with 1:1 AVC and appropriately switched to VDD during AV block. No pacing safety issues were observed during arrhythmias.

Matched MeSH terms: Heart Rate
Dental caries in Malaysian children with heart defects

Johnson RO, Grieve AW

Med J Malaysia, 1978 Sep;33(1):44-6.
PMID: 750895
Matched MeSH terms: Heart Defects, Congenital/complications*; Rheumatic Heart Disease/complications*
Fulltext Distinct position of chaotic pulse trains observed in Malaysia

Chandima Gomes, Muhammad Noh Hamzah

Pertanika Journal of Science & Technology, 2017;25(102):53-60.
MyJurnal

This paper presents the chaotic pulse train (CPT) waveforms of the vertical electric field generated by lightning observed in Malaysia. Focusing on the position where these electric field changes occur in a number of cloud to ground (CG) flashes, these CPTs were detected in different ways of occurrences, durations, intensities and amplitudes. Seventy-six chaotic pulse trains were found in this study from a sum of 172 CG flash records from three thunderstorm days. The fast field antenna was employed to do the field measurements. As opposed to the typical occurrence of chaotic pulse trains prior to subsequent strokes as reported in the literature, this study has found chaotic pulse trains occurring in different places along the CG electric field waveforms.

Matched MeSH terms: Heart Rate
Fulltext Investigating insulator UV signal frequency components as potential tools for condition monitoring of ceramic insulators

Saiful Mohammad Iezham Suhaimi, Nouruddeen Bashir, Nor Asiah Muhamad, Mohd Aizam Talib

Pertanika Journal of Science & Technology, 2017;25(102):291-298.
MyJurnal

Contaminated and ageing transmission line insulators often suffer from temporary or permanent loss of their insulating properties due to flashover resulting in power system failure. Surface discharges are precursors to flashover. To pre-empt any occurrence of flashovers, utility companies monitor the conditions of their insulators. There are numerous insulator surface monitoring techniques such as Leakage Current, Acoustics, and Infrared. However, these techniques may not be suitable for in-situ condition monitoring of the insulators as they are prone to noise, affected by environmental conditions or contact methods. Monitoring of the UV signals emitted by the surface discharges of these insulators has been reported to be a promising technique. However, comprehensive studies on this technique is lacking, especially on aged insulators. This paper investigated the UV signals of contaminated and aged insulators detected during surface discharge activities using UV pulse method. The time and frequency domain of the UV signals were analysed for a group of insulator samples having varying levels of contamination and phases of ageing. Results show that there is a strong correlation between the contamination level and ageing of the insulators with the amplitude and harmonic components of the UV signals. This correlation can useful to monitor in-service insulator surface conditions.

Matched MeSH terms: Heart Rate
A novel automated diagnostic system for classification of myocardial infarction ECG signals using an optimal biorthogonal filter bank

Sharma M, Tan RS, Acharya UR

Comput Biol Med, 2018 11 01;102:341-356.
PMID: 30049414 DOI: 10.1016/j.compbiomed.2018.07.005

Myocardial infarction (MI), also referred to as heart attack, occurs when there is an interruption of blood flow to parts of the heart, due to the acute rupture of atherosclerotic plaque, which leads to damage of heart muscle. The heart muscle damage produces changes in the recorded surface electrocardiogram (ECG). The identification of MI by visual inspection of the ECG requires expert interpretation, and is difficult as the ECG signal changes associated with MI can be short in duration and low in magnitude. Hence, errors in diagnosis can lead to delay the initiation of appropriate medical treatment. To lessen the burden on doctors, an automated ECG based system can be installed in hospitals to help identify MI changes on ECG. In the proposed study, we develop a single-channel single lead ECG based MI diagnostic system validated using noisy and clean datasets. The raw ECG signals are taken from the Physikalisch-Technische Bundesanstalt database. We design a novel two-band optimal biorthogonal filter bank (FB) for analysis of the ECG signals. We present a method to design a novel class of two-band optimal biorthogonal FB in which not only the product filter but the analysis lowpass filter is also a halfband filter. The filter design problem has been composed as a constrained convex optimization problem in which the objective function is a convex combination of multiple quadratic functions and the regularity and perfect reconstruction conditions are imposed in the form linear equalities. ECG signals are decomposed into six subbands (SBs) using the newly designed wavelet FB. Following to this, discriminating features namely, fuzzy entropy (FE), signal-fractal-dimensions (SFD), and renyi entropy (RE) are computed from all the six SBs. The features are fed to the k-nearest neighbor (KNN). The proposed system yields an accuracy of 99.62% for the noisy dataset and an accuracy of 99.74% for the clean dataset, using 10-fold cross validation (CV) technique. Our MI identification system is robust and highly accurate. It can thus be installed in clinics for detecting MI.

Matched MeSH terms: Heart
Extensive left ventricular, pulmonary artery, and pericardial metastasis from myxoid liposarcoma 16 years after the initial detection of the primary tumour: a case report and review of the literature

Motevalli D, Tavangar SM

Malays J Pathol, 2017 Aug;39(2):201-205.
PMID: 28866706

Liposarcoma is regarded as the second most common soft tissue malignant tumour. Metastasis of liposarcoma to the heart is very rare, and to date, less than 40 cases have been reported in the literature. We report a 46 year-old male with myxoid liposarcoma of the lower extremity who developed extensive metastasis to the left ventricle, pulmonary artery, and pericardium. The patient presented with acute symptoms of dyspnea 16 years after surgical resection of the primary tumour, and his dyspnea progressed to cardio-respiratory arrest within the first few days of hospital admission.

Matched MeSH terms: Heart Neoplasms/secondary*; Heart Ventricles/pathology
Fulltext Basics of electrocardiogram (ECG) and its application in diagnosis of heart ailments: an educational series

Chodankar, Nagesh N., May, Honey Ohn, D’Souza, Urban John Arnold

Borneo Journal of Medical Sciences, 2018;12(1):3-22.
MyJurnal

Electrocardiogram (ECG) is a record of electrical activity of the heart. PQRST waves represent
the electrical activities of atria and ventricles. A complete three-dimensional electrical activity is
possible to be recorded using a 12-lead ECG. The normal and different routinely-met clinical ECG
are elaborated and discussed. This routine, normal and abnormal ECG, like arrhythmias and heart
block records as well as their clinical notes shall be educational information for the medical students.

Matched MeSH terms: Heart Atria
Arrhythmia detection using deep convolutional neural network with long duration ECG signals

Yıldırım Ö, Pławiak P, Tan RS, Acharya UR

Comput Biol Med, 2018 11 01;102:411-420.
PMID: 30245122 DOI: 10.1016/j.compbiomed.2018.09.009

This article presents a new deep learning approach for cardiac arrhythmia (17 classes) detection based on long-duration electrocardiography (ECG) signal analysis. Cardiovascular disease prevention is one of the most important tasks of any health care system as about 50 million people are at risk of heart disease in the world. Although automatic analysis of ECG signal is very popular, current methods are not satisfactory. The goal of our research was to design a new method based on deep learning to efficiently and quickly classify cardiac arrhythmias. Described research are based on 1000 ECG signal fragments from the MIT - BIH Arrhythmia database for one lead (MLII) from 45 persons. Approach based on the analysis of 10-s ECG signal fragments (not a single QRS complex) is applied (on average, 13 times less classifications/analysis). A complete end-to-end structure was designed instead of the hand-crafted feature extraction and selection used in traditional methods. Our main contribution is to design a new 1D-Convolutional Neural Network model (1D-CNN). The proposed method is 1) efficient, 2) fast (real-time classification) 3) non-complex and 4) simple to use (combined feature extraction and selection, and classification in one stage). Deep 1D-CNN achieved a recognition overall accuracy of 17 cardiac arrhythmia disorders (classes) at a level of 91.33% and classification time per single sample of 0.015 s. Compared to the current research, our results are one of the best results to date, and our solution can be implemented in mobile devices and cloud computing.

Matched MeSH terms: Heart Diseases
Fulltext Analysis of Phase-Shift Pulse Brillouin Optical Time-Domain Reflectometry

Horiguchi T, Masui Y, Zan MSD

Sensors (Basel), 2019 Mar 27;19(7).
PMID: 30934806 DOI: 10.3390/s19071497

Distributed strain and temperature can be measured by using local Brillouin backscatter in optical fibers based on the strain and temperature dependence of the Brillouin frequency shift. The technique of analyzing the local Brillion backscatter in the time domain is called Brillouin optical time domain reflectometry (BOTDR). Although the best spatial resolution of classic BOTDR remains at around 1 m, some recent BOTDR techniques have attained as high as cm-scale spatial resolution. Our laboratory has proposed and demonstrated a high-spatial-resolution BOTDR called phase-shift pulse BOTDR (PSP-BOTDR), using a pair of probe pulses modulated with binary phase-shift keying. PSP-BOTDR is based on the cross-correlation of Brillouin backscatter and on the subtraction of cross-correlations obtained from the Brillouin scatterings evoked by each phase-modulated probe pulse. Although PSP-BOTDR has attained 20-cm spatial resolution, the spectral analysis method of PSP-BOTDR has not been discussed in detail. This article gives in-depth analysis of the Brillouin backscatter and the correlations of the backscatters of the PSP-BOTDR. Based on the analysis, we propose new spectral analysis methods for PSP-BOTDR. The analysis and experiments show that the proposed methods give better frequency resolution than before.

Matched MeSH terms: Heart Rate
Fulltext Rheumatic heart disease in referred cases: Experience at a cardiology centre

Jamal F, Abdullah N, Zambahari R

Family Practitioner, 1988;11(1):46-47.

Matched MeSH terms: Rheumatic Heart Disease
Computerized assisted evaluation system for canine cardiomegaly via key points detection with deep learning

Zhang M, Zhang K, Yu D, Xie Q, Liu B, Chen D, et al.

Prev Vet Med, 2021 Aug;193:105399.
PMID: 34118647 DOI: 10.1016/j.prevetmed.2021.105399

Cardiomegaly is the main imaging finding for canine heart diseases. There are many advances in the field of medical diagnosing based on imaging with deep learning for human being. However there are also increasing realization of the potential of using deep learning in veterinary medicine. We reported a clinically applicable assisted platform for diagnosing the canine cardiomegaly with deep learning. VHS (vertebral heart score) is a measuring method used for the heart size of a dog. The concrete value of VHS is calculated with the relative position of 16 key points detected by the system, and this result is then combined with VHS reference range of all dog breeds to assist in the evaluation of the canine cardiomegaly. We adopted HRNet (high resolution network) to detect 16 key points (12 and four key points located on vertebra and heart respectively) in 2274 lateral X-ray images (training and validation datasets) of dogs, the model was then used to detect the key points in external testing dataset (396 images), the AP (average performance) for key point detection reach 86.4 %. Then we applied an additional post processing procedure to correct the output of HRNets so that the AP reaches 90.9 %. This result signifies that this system can effectively assist the evaluation of canine cardiomegaly in a real clinical scenario.

Matched MeSH terms: Heart

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