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Fetal heart rate monitoring based on independent component analysis

Najafabadi FS, Zahedi E, Mohd Ali MA

Comput Biol Med, 2006 Mar;36(3):241-52.
PMID: 16446158

In this paper, an algorithm based on independent component analysis (ICA) for extracting the fetal heart rate (FHR) from maternal abdominal electrodes is presented. Three abdominal ECG channels are used to extract the FHR in three steps: first preprocessing procedures such as DC cancellation and low-pass filtering are applied to remove noise. Then the algorithm for multiple unknown source extraction (AMUSE) algorithm is fed to extract the sources from the observation signals include fetal ECG (FECG). Finally, FHR is extracted from FECG. The method is shown to be capable of completely revealing FECG R-peaks from observation leads even with a SNR=-200dB using semi-synthetic data.

Matched MeSH terms: Heart Rate, Fetal*
Transcatheter closure of muscular ventricular septal defect using the Amplatzer devices

Djer MM, Latiff HA, Alwi M, Samion H, Kandavello G

Heart Lung Circ, 2006 Feb;15(1):12-7.
PMID: 16473785

From November 1997 to June 2002, percutaneous transcatheter closure of muscular ventricular septal defects was attempted in seven patients. Four patients had single and three had multiple defects. Surgical closure was performed in two patients in an attempt to close a perimembranous defect, leaving behind a large apical muscular defect, which was successfully closed using a device in one patient, whilst the second patient succumbed to septicemia/endocarditis 3 weeks after failure of device implantation. One patient had previous pulmonary artery banding and in another intraoperative placement of two Clamshell devices followed by additional transcatheter closure using Gianturco coils in two different sessions was performed.

Matched MeSH terms: Heart Septal Defects, Ventricular/surgery*
Stem cells and injectable hydrogels: Synergistic therapeutics in myocardial repair

Sepantafar M, Maheronnaghsh R, Mohammadi H, Rajabi-Zeleti S, Annabi N, Aghdami N, et al.

Biotechnol Adv, 2016 Jul-Aug;34(4):362-379.
PMID: 26976812 DOI: 10.1016/j.biotechadv.2016.03.003

One of the major problems in the treatment of cardiovascular diseases is the inability of myocardium to self-regenerate. Current therapies are unable to restore the heart's function after myocardial infarction. Myocardial tissue engineering is potentially a key approach to regenerate damaged heart muscle. Myocardial patches are applied surgically, whereas injectable hydrogels provide effective minimally invasive approaches to recover functional myocardium. These hydrogels are easily administered and can be either cell free or loaded with bioactive agents and/or cardiac stem cells, which may apply paracrine effects. The aim of this review is to investigate the advantages and disadvantages of injectable stem cell-laden hydrogels and highlight their potential applications for myocardium repair.

Matched MeSH terms: Heart/physiology
Arrhythmia recognition and classification using combined linear and nonlinear features of ECG signals

Elhaj FA, Salim N, Harris AR, Swee TT, Ahmed T

Comput Methods Programs Biomed, 2016 Apr;127:52-63.
PMID: 27000289 DOI: 10.1016/j.cmpb.2015.12.024

Arrhythmia is a cardiac condition caused by abnormal electrical activity of the heart, and an electrocardiogram (ECG) is the non-invasive method used to detect arrhythmias or heart abnormalities. Due to the presence of noise, the non-stationary nature of the ECG signal (i.e. the changing morphology of the ECG signal with respect to time) and the irregularity of the heartbeat, physicians face difficulties in the diagnosis of arrhythmias. The computer-aided analysis of ECG results assists physicians to detect cardiovascular diseases. The development of many existing arrhythmia systems has depended on the findings from linear experiments on ECG data which achieve high performance on noise-free data. However, nonlinear experiments characterize the ECG signal more effectively sense, extract hidden information in the ECG signal, and achieve good performance under noisy conditions. This paper investigates the representation ability of linear and nonlinear features and proposes a combination of such features in order to improve the classification of ECG data. In this study, five types of beat classes of arrhythmia as recommended by the Association for Advancement of Medical Instrumentation are analyzed: non-ectopic beats (N), supra-ventricular ectopic beats (S), ventricular ectopic beats (V), fusion beats (F) and unclassifiable and paced beats (U). The characterization ability of nonlinear features such as high order statistics and cumulants and nonlinear feature reduction methods such as independent component analysis are combined with linear features, namely, the principal component analysis of discrete wavelet transform coefficients. The features are tested for their ability to differentiate different classes of data using different classifiers, namely, the support vector machine and neural network methods with tenfold cross-validation. Our proposed method is able to classify the N, S, V, F and U arrhythmia classes with high accuracy (98.91%) using a combined support vector machine and radial basis function method.

Matched MeSH terms: Heart; Heart Defects, Congenital
Fulltext A case of successful extracorporeal membrane oxygenation for right ventricular failure following pericardiectomy

Karthigesu A, Hamdan L, Arif M, Haslan G

Med J Malaysia, 2015 Dec;70(6):369-70.
PMID: 26988215 MyJurnal

Extracorporeal membrane oxygenation (ECMO) is a useful but less commonly used technique in right ventricular failure post cardiac surgery in our region. We report a case of successful use of ECMO for right ventricular failure post cardiac surgery. Our patient is a 27-year-old male presented with constrictive pericarditis post completion of treatment for disseminated Tuberculosis. He underwent pericardiectomy that was complicated with acute right ventricular failure. He was placed on extracorporeal membrane oxygenation after few hours post op that lasted for five days. The patient survived to hospital discharge and remained well on follow-up. From our experience, this aggressive management approach is beneficial in right ventricular failure and can be safely utilised in all cardiothoracic centres.

Matched MeSH terms: Heart; Heart Failure
Sodium channel haploinsufficiency and structural change in ventricular arrhythmogenesis

Jeevaratnam K, Guzadhur L, Goh YM, Grace AA, Huang CL

Acta Physiol (Oxf), 2016 Feb;216(2):186-202.
PMID: 26284956 DOI: 10.1111/apha.12577

Normal cardiac excitation involves orderly conduction of electrical activation and recovery dependent upon surface membrane, voltage-gated, sodium (Na(+) ) channel α-subunits (Nav 1.5). We summarize experimental studies of physiological and clinical consequences of loss-of-function Na(+) channel mutations. Of these conditions, Brugada syndrome (BrS) and progressive cardiac conduction defect (PCCD) are associated with sudden, often fatal, ventricular tachycardia (VT) or fibrillation. Mouse Scn5a(+/-) hearts replicate important clinical phenotypes modelling these human conditions. The arrhythmic phenotype is associated not only with the primary biophysical change but also with additional, anatomical abnormalities, in turn dependent upon age and sex, each themselves exerting arrhythmic effects. Available evidence suggests a unified binary scheme for the development of arrhythmia in both BrS and PCCD. Previous biophysical studies suggested that Nav 1.5 deficiency produces a background electrophysiological defect compromising conduction, thereby producing an arrhythmic substrate unmasked by flecainide or ajmaline challenge. More recent reports further suggest a progressive decline in conduction velocity and increase in its dispersion particularly in ageing male Nav 1.5 haploinsufficient compared to WT hearts. This appears to involve a selective appearance of slow conduction at the expense of rapidly conducting pathways with changes in their frequency distributions. These changes were related to increased cardiac fibrosis. It is thus the combination of the structural and biophysical changes both accentuating arrhythmic substrate that may produce arrhythmic tendency. This binary scheme explains the combined requirement for separate, biophysical and structural changes, particularly occurring in ageing Nav 1.5 haploinsufficient males in producing clinical arrhythmia.

Matched MeSH terms: Heart/physiopathology*
On the binaural brain entrainment indicating lower heart rate variability

Palaniappan R, Phon-Amnuaisuk S, Eswaran C

Int J Cardiol, 2015;190:262-3.
PMID: 25932800 DOI: 10.1016/j.ijcard.2015.04.175
Matched MeSH terms: Heart Rate/physiology*
Fulltext Preload-based starling-like control for rotary blood pumps: numerical comparison with pulsatility control and constant speed operation

Mansouri M, Salamonsen RF, Lim E, Akmeliawati R, Lovell NH

PLoS One, 2015;10(4):e0121413.
PMID: 25849979 DOI: 10.1371/journal.pone.0121413

In this study, we evaluate a preload-based Starling-like controller for implantable rotary blood pumps (IRBPs) using left ventricular end-diastolic pressure (PLVED) as the feedback variable. Simulations are conducted using a validated mathematical model. The controller emulates the response of the natural left ventricle (LV) to changes in PLVED. We report the performance of the preload-based Starling-like controller in comparison with our recently designed pulsatility controller and constant speed operation. In handling the transition from a baseline state to test states, which include vigorous exercise, blood loss and a major reduction in the LV contractility (LVC), the preload controller outperformed pulsatility control and constant speed operation in all three test scenarios. In exercise, preload-control achieved an increase of 54% in mean pump flow ([Formula: see text]) with minimum loading on the LV, while pulsatility control achieved only a 5% increase in flow and a decrease in mean pump speed. In a hemorrhage scenario, the preload control maintained the greatest safety margin against LV suction. PLVED for the preload controller was 4.9 mmHg, compared with 0.4 mmHg for the pulsatility controller and 0.2 mmHg for the constant speed mode. This was associated with an adequate mean arterial pressure (MAP) of 84 mmHg. In transition to low LVC, [Formula: see text] for preload control remained constant at 5.22 L/min with a PLVED of 8.0 mmHg. With regards to pulsatility control, [Formula: see text] fell to the nonviable level of 2.4 L/min with an associated PLVED of 16 mmHg and a MAP of 55 mmHg. Consequently, pulsatility control was deemed inferior to constant speed mode with a PLVED of 11 mmHg and a [Formula: see text] of 5.13 L/min in low LVC scenario. We conclude that pulsatility control imposes a danger to the patient in the severely reduced LVC scenario, which can be overcome by using a preload-based Starling-like control approach.

Matched MeSH terms: Heart-Assist Devices*
A fatal nail gun injury--an unusual ricochet?

Nadesan K

Med Sci Law, 2000 Jan;40(1):83-7.
PMID: 10689867

An 18-year-old construction worker suddenly collapsed while handling a power-actuated nail gun and died shortly after. A neat, almost circular puncture wound was found on the front of his left chest. No fire-arm residues were detected on the surrounding skin. The police stated that it was an accidental injury, at a construction site, where a nail fired from a nail gun by the deceased had deflected off the wall and struck him on the front of the chest. Since the entry wound appeared to be a neat hole, and that too on the front of the left chest overlying the heart area, there was reluctance on the part of the pathologist to accept it as an accidental injury due to a ricochet. A visit to the scene, interrogation of witnesses, examination of the alleged tool and post-mortem X-ray of the deceased were undertaken prior to autopsy. A bent nail was found in the heart. The scene visit and the subsequent autopsy revealed that the nail took a roughly circular flightpath after it had struck the wall, all the while travelling with its pointed end directed forward. Within the body too, the nail maintained the same path. Various medicolegal issues are discussed pertaining to nail-gun injuries. The importance of a visit to the scene, examination of the alleged tool, interrogation of witnesses and the X-ray of the body, all prior to autopsy, are emphasized. The conclusion was: accidental death due to the unusual ricochet of a nail.

Matched MeSH terms: Heart Injuries/etiology*
Fulltext Penetrating cardiac injury without tamponade

Aung T

Med J Malaysia, 1997 Dec;52(4):441-3.
PMID: 10968125

A case of unsuspected penetrating cardiac injury is presented. It was recognised by the presence of bleeding into peritoneal cavity even after the source of bleeding from intra-abdominal organs had been stopped. It highlights the importance of high index of suspicion of associated cardiac injury in high epigastric penetrating injury.

Matched MeSH terms: Heart Injuries/diagnosis*
The value of transesophageal echocardiography in transcatheter closure of atrial septal defects in the oval fossa using the Amplatzer septal occluder

Latiff HA, Samion H, Kandhavel G, Aziz BA, Alwi M

Cardiol Young, 2001 Mar;11(2):201-4.
PMID: 11293739

BACKGROUND: From January, 1997, as part of an international multicentric trial, we have been closing small-to-moderate atrial septal defects within the oval fossa using the Amplatzer Septal Occluder (ASO, AGA Medical).
METHODS: All patients with defects within the oval fossa deemed potentially suitable for transcatheter closure were investigated by transesophageal echocardiography with the aim of gaining extra information that might alter the decision to use the device to close the defect. Views were obtained in transverse and longitudinal planes, permitting measurements of the diameter of the defect, and its distance from the atrioventricular valves, coronary sinus, and pulmonary veins. Additionally, we sought to identify multiple defects, and to exclude sinus venosus defects.
RESULTS: Of 56 patients with left-to-right shunts, 41 (73.2%) were deemed suitable for closure with the Amplatzer Septal Occluder. All underwent the procedure successfully, with no complications. This includes 5 patients with multiple small defects that were sufficiently close to the main defect to be closed with a single device. Only two of these had been detected on the transthoracic study. In the remaining 15 of 56 patients, transcatheter closure was deemed unsuitable. In 9 patients, this was due to the limitation of the size of the device available during the period of study, this representing a relative contraindication. In the remaining 6 (10.7%), transcatheter closure was not performed because multiple defects were too far apart to be closed with a single device in 3 patients, two patients were noted to have a sinus venosus defect, and another was noted to have anomalous connection of the right upper pulmonary vein to the right atrium. Excluding patients contraindicated due to the size of the defect alone, transesophageal echocardiography provided extra information in one-tenth of our patients, which altered the decision regarding management.
CONCLUSION: Transesophageal echocardiography is indispensable in the evaluation of patients undergoing transcatheter closure of atrial septal defect.

Matched MeSH terms: Heart Septal Defects, Atrial/therapy*
Fetal cerebral Doppler in the recognition of fetal compromise

Chandran R, Serra-Serra V, Sellers SM, Redman CW

Br J Obstet Gynaecol, 1993 Feb;100(2):139-44.
PMID: 8476805

OBJECTIVE: To establish reference ranges for the human fetal middle cerebral artery pulsatility index (MCA PI) for the local obstetric population, and to compare computerised antenatal fetal heart rate (FHR) analysis with the MCA PI as indicators of fetal compromise.
DESIGN: Prospective data collection for selected patients.
SETTING: High risk pregnancy unit of a teaching hospital.
SUBJECTS: Group 1 consisted of 18 healthy women with uncomplicated singleton pregnancies. Group 2 consisted of 27 women admitted to the high risk pregnancy unit over a 9 month period with intrauterine growth retardation and other related problems; all these women were delivered by prelabour caesarean section.
INTERVENTION: Serial Duplex sonography to determine fetal MCA PI in Groups 1 and 2. Serial FHR analysis using computerised numerical techniques in Group 2 only.
MAIN OUTCOME MEASURES: Serial MCA PI values from 24 to 39 completed weeks of gestation in Group 1. Comparison of serial MCA PI values with FHR analysis in relation to fetal outcome in Group 2.
RESULTS: In Group 1 the MCA PI diminished significantly as gestation advanced from 1.73 (SD 0.25) at 24 weeks to 1.38 (SD 0.26) at 39 weeks (P < 0.01). In Group 2 eleven babies were hypoxaemic at delivery: all had low MCA PI values while only nine had an abnormal FHR prior to delivery.
CONCLUSION: In normal pregnancy, there is a fall in the fetal MCA PI with advancing gestation which probably reflects a decreasing vascular resistance to fetal cerebral blood flow. Hypoxaemia at delivery appeared to be better recognised by the fetal MCA flow velocity waveform than the FHR analysis. This increased sensitivity, however, was achieved at the expense of a reduced specificity. Larger studies are needed to confirm the findings of this preliminary investigation.

Matched MeSH terms: Heart Rate, Fetal/physiology*
Group A streptococcal infections

Jamal F

Malays J Pathol, 1996 Jun;18(1):15-6.
PMID: 10879218
Matched MeSH terms: Rheumatic Heart Disease/etiology
Fulltext Cor pulmonale due to obstructive sleep apnoea

Liam CK

Med J Malaysia, 1993 Sep;48(3):347-50.
PMID: 8183151

A 47 year old man with a long history of chronic loud snoring and daytime sleepiness presented with hypercapnic respiratory failure and right ventricular failure. The diagnosis of obstructive sleep apnoea (OSA) leading to the 'obesity-hypoventilation syndrome', was supported by the findings of an overnight cardio-respiratory monitoring during sleep. His symptoms and arterial blood gases improved following treatment with nocturnal nasal continuous positive airway pressure (CPAP).

Matched MeSH terms: Pulmonary Heart Disease/etiology*
Doppler-echocardiographic assessment of Carbomedics prosthetic values in the mitral position

Soo CS, Ca M, Tay M, Yeoh JK, Sim E, Choo M

J Am Soc Echocardiogr, 1994 3 1;7(2):159-64.
PMID: 8185960

We prospectively studied 37 consecutive patients implanted with the Carbomedics prosthetic heart value in the mitral position (without clinical evidence of prosthetic valve dysfunction) with two-dimensional and Doppler echocardiography. The peak mitral prosthetic gradient ranged from 4.60 to 14.63 (mean 8.97 +/- 2.29) mm Hg; mean mitral prosthetic gradient ranged from 1.67 to 6.18 (mean 3.24 +/- 0.95) mm Hg; pressure half-time derived mitral valve area ranged from 1.67 to 5.30 (mean 2.70 +/- 0.80) cm2. These values compare favorably with that of another bileaflet valve (i.e., the St. Jude Medical valve). There was a wide overlap in peak and mean transmitral gradients, even with the valves of the same size, with a significant but weak inverse relationship between peak mitral gradients and valve size (p = 0.03, r = -0.36). The performance index showed a smaller range of values, again with a significant but weak inverse relationship with valve size (p = 0.001, r = -0.54). The inverse relationship between valve size and peak mitral gradient and performance index should be borne in mind when analyzing Doppler hemodynamic data.

Matched MeSH terms: Heart Valve Prosthesis*
Fulltext A case of left atrial myxoma

Segasothy M

Med J Malaysia, 1982 Sep;37(3):221-2.
PMID: 7177002

Left atrial myxoma almost always arises in the inter-atrial septum. A case is described where it arose from the posterior wall of the left atrium. Clinical presentation was suggestive of mitral stenosis and sub-acute bacterial endocarditis and diagnosis was arrived at necropsy.

Matched MeSH terms: Heart Neoplasms/diagnosis*
Fulltext Systemic scleroderma with complete heart block

Anuar M, Singham KT

Med J Malaysia, 1983 Mar;38(1):65-7.
PMID: 6633341
Matched MeSH terms: Heart Block/complications*
Fulltext The leopard (multiple lentigines) syndrome: a case report

Ting HC, Ng SC

Med J Malaysia, 1983 Jun;38(2):98-101.
PMID: 6621454

A case of the leopard (multiple lentigines) syndrome is described. To our knowledge this is the first documented case of this rare but interesting syndrome to be reported in this country.

Matched MeSH terms: Heart Defects, Congenital/complications*
Cardiac arrest following an intravenous urogram--a case report

Chan CP

Med J Malaysia, 1977 Dec;32(2):147-8.
PMID: 614481
Matched MeSH terms: Heart Arrest/etiology*
Fulltext Dynamic cervical lung lobe herniation in a shih tzu dog

Joanne, T.S.Y., Lim, M.L., Asnawi, O., Shamsul, M.A.H., Khor, K.H.

Jurnal Veterinar Malaysia, 2019;31(1):38-42.
MyJurnal

An 8-year-old spayed female Shih Tzu was referred to University Veterinary Hospital (UVH) with history of chronic coughing for more than a year duration. Dry, hacking cough was heard and bilateral wheezing lung sound was noted upon physical examination. Auscultation of heart revealed left apical systolic heart murmur Grade III/VI. A soft, intermittent swelling was observed at ventral neck, cranial to thoracic inlet (protruded upon expiration and collapsed upon inspiration). Thoracic radiography taken showed presence of apical radiolucency at cervical region and bronchial pattern at caudodorsal lungs with left atrium enlargement and right-sided heart enlargement. Echocardiographic examination revealed myxomatous mitral valve disease (MMVD) with mild regurgitation. Based on diagnostic imaging, this case was diagnosed as dynamic lung lobe herniation secondary to chronic coughing concurrent with myxomatous mitral valve disease. Other differential diagnosis that may lead to chronic cough such as of tracheal collapsed and bronchiectasis was not rule out.

Matched MeSH terms: Heart Atria; Heart Murmurs

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