The Application of Biomedical Engineering Techniques to the Diagnosis and Management of Tropical Diseases: A Review <s> Echocardiography and Electrocardiography (ECG) <s> Acute shock in severe dengue haemorrhagic fever (DHF) may occur concurrently with accumulation of fluid in serous body spaces such as pleural, peritoneal and pericardial cavities. Echocardiography is a non-invasive diagnostic procedure which is sensitive to detect even a small quantity of pericardial effusion. The chest radiogram in two reported cases of DHF associated with severe shock revealed that almost half of the pleural cavity was filled with fluid. Although no signs of pericardial effusion could be determined on physical examination, ECG and radiological procedures, a small amount of fluid was clearly seen on echocardiogram. <s> BIB001 </s> The Application of Biomedical Engineering Techniques to the Diagnosis and Management of Tropical Diseases: A Review <s> Echocardiography and Electrocardiography (ECG) <s> Abstract We studied 17 consecutive patients of Dengue Haemorrhagic Fever/Dengue Shock Syndrome (DHF/DSS) to assess cardiac function by radionuclide ventriculography, echocardiography and electrocardiography (ECG) during the epidemic of Dengue virus type-2 (DEN-2) in Delhi, India (1996). Case definitions laid down by the WHO were followed. Fourteen patients were seropositive for Dengue infection. In radionuclide ventriculography study, the mean left-ventricular ejection fraction was 41.69 (5.04% (range 33–49%) and 7 patients had an ejection fraction less than 40%, global hypokinesia was detected in 12 (70.59%) patients. In echocardiography, the mean ejection fraction was 47.06 (3.8%). Eight patients had Dengue Shock Syndrome and the mean ejection fraction was 39.63% (4.97% in radionuclide ventriculography, out of which 5 patients had an ejection fraction below 40%. To find out the nature of myocardial involvement, 99m Tc-pyrophosphate imaging was done in 4 patients and it was discontinued further because no myocardial necrosis was detected in those patients. Five patients had ST and T changes in the electrocardiogram, radionuclide ventriculography and echocardiography revealed no abnormalities after 3 weeks of follow up and the ejection fraction was more than 50% in all cases. Global hypokinesia also improved and ECG changes reverted back to normal within 3 weeks. Acute reversible cardiac insult may be noticed in Dengue Haemorrhagic Fever/Dengue Shock Syndrome and could be responsible for hypotension/shock seen in some of these patients. Further studies are required to establish the pathogenic mechanisms of cardiac dysfunction in patients with Dengue Haemorrhagic Fever/Dengue Shock Syndrome. <s> BIB002
Echocardiography and electrocardiography (ECG) were utilized in several studies to assess cardiac function of dengue patients BIB001 BIB002  . Acute shock in severe DHF cases may occur in parallel with accumulation of fluid in serous body spaces such as the pleural, peritoneal, and pericardial cavities BIB001 . Pelupessy et al. BIB001 investigated the implementation of echocardiography in diagnosing dengue patients since echocardiography is a very sensitive method for detecting any small quantity of pericardial effusion The study showed that, although no signs of pericardial effusion could be determined on physical examination of DHF patients associated with severe shock and through ECG and radiological procedures, echocardiogram results were able to clearly show a small amount of fluid. Thus this technique is only recommended for the application of acute shock dengue patients. In 1998, Wali et al. BIB002 employed radionuclide ventriculography, echocardiography, and ECG to assess cardiac function of 17 DHF and DSS patients. The radionuclide ventriculography results revealed that, the mean left-ventricular ejection fraction was 41.69%. Seven patients had an ejection fraction of less than 40%. Global hypokinesia was detected in 70.59% of the patients. The echocardiography results showed that the mean ejection fraction was 47.06%. The mean ejection fraction of the 8 DSS patients was 39.63%. Five (67.5%) of those patients had an ejection fraction below 40%. Radionuclide ventriculography and echocardiography showed no abnormalities after 3 weeks of follow up for five patients who had ST and T changes in their electrocardiogram. The ejection fraction was more than 50% in these cases. Within 3 weeks, the Global hypokinesia also improved and ECG changes reverted back to normal. The study concluded that acute reversible cardiac insult may be noticed in DHF/DSS and could be responsible for hypotension/shock seen in some of these patients. It was recommended that further studies are carried out to establish the pathogenic mechanisms of cardiac dysfunction in patients with DHF and DSS. In 1993, Yusoff et al.  performed echocardiograms and ECGs on 28 consecutive adult patients with a clinical diagnosis of dengue infection. Twenty-three dengue patients were serologically confirmed (22 DHF grades I and II; 1 DF). 87% of the serologically confirmed dengue patients had abnormal ECGs and/or echocardiograms. Of these, 65% had abnormal ECGs that consisted of conduction abnormalities, ST segment elevation, T wave inversion, and sinus bradycardia. Fifty-two percent had abnormal echocardiograms which showed pericardial effusion, abnormal systolic and diastolic functions, left ventricular dilatation, and tricuspid regurgitation. The authors declared that ECG and echocardiographic abnormalities are common during the acute phase of DHF. They recommended early detection of cardiac involvement as a way of identifying the more severe forms of dengue so that appropriate treatment can be initiated as early as possible.