Original Article

Ramakrishna CD, Khadar SA, George R, Jayaprakash VL, Sudhayakumar N, Jayaprakash K, Pappachan JM
Correspondence: Dr Joseph M Pappachan, drpappachan@yahoo.co.in

ABSTRACT
Introduction This cross-sectional study on the age-specific clinical and anatomical characteristics of mitral stenosis was conducted at the Department of Cardiology at Kottayam Medical College, South India.
Methods The clinical profile, laboratory details and transthoracic echocardiographical features of 203 consecutive patients with mitral stenosis were studied. Wilkins score was used to assess the valve morphology and the feasibility of balloon mitral valvotomy (BMV)/closed mitral valvotomy (CMV). Patients were grouped according to age, into Group I (younger than 40 years; 68 cases), Group II (40–65 years; 78 cases) and Group III (older than 65 years; 57 cases) for analysis.
Results The mean age of the patients was 53 years. History of rheumatic fever was less common in Group III (37 percent in Group I vs. 20 percent in Group III, p-value is equal to 0.05). Acute pulmonary oedema occurred commonly in Group III (six percent in Group I vs. 36 percent in Group III, p-value is less than 0.001). Incidence of ischaemic strokes increased with increasing age (three percent in Group I vs. 12 percent in Group II, p-value is equal to 0.05; 12 percent in Group II vs. 25 percent in Group III, p-value is equal to 0.05; and three percent in Group I vs. 25 percent in Group III, p-value is less than 0.001). Prevalence of atrial fibrillation (AF) increased progressively with increasing age (nine percent in Group I vs. 30 percent in Group II, p-value is less than 0.001; 30 percent in Group II vs. 64 percent in Group III, p-value equal to 0.003). Clinical features of pulmonary hypertension was highest among Group I (66 percent in Group I vs. 42 percent and 43 percent in Groups II and III, respectively, p-value is equal to 0.01). The mean duration of exertional dyspnoea, history of paroxysmal nocturnal dyspnoea, mean NYHA class, mean left atrial sizes, mean mitral valve areas and mean mitral valve gradients did not vary significantly among the three groups. Mitral valve scores were prohibitive for BMV/CMV in significant numbers of older patients (seven percent in Group I vs. 38 percent in Group II vs. 80 percent in Group III; p-value is less than 0.001).
Conclusion When compared to the trends in developed countries, the mean age at presentation of mitral stenosis is similar, but the degree of valve deformity is higher. Incidence of pulmonary oedema, AF and stroke increases with advancing age in mitral stenosis.

Keywords: atrial fibrillation, mitral stenosis, mitral valvotomy, pulmonary oedema, rheumatic heart disease, stroke
Singapore Med J 2009; 50(7): 680-685

Chang G, Luo HD, Emmert MY, Lee CN, Kofidis T
Correspondence: Dr Theo Kofidis, surtk@nus.edu.sg

ABSTRACT
Introduction Stroke is a debilitating complication of cardiac surgery. Many intraoperative and postoperative factors predict the likelihood of post-cardiac surgery stroke. We evaluated preoperative parameters, seeking correlations with adverse neurological outcome following cardiac surgery. We investigated the possibility of preoperative carotid ultrasonography to select patients for carotid endarterectomy pre-or intraoperatively.
Methods We conducted a retrospective analysis of 61 patients who suffered stroke post-cardiac surgery from 2003 to 2006. Data was collected for patient and disease characteristics, preoperative status, intraoperative events and postoperative course. Postoperative neurological complications were sub divided into three groups: mild/temporary events, moderate events such as seizures, and severe events such as stroke. A mild/temporary event was defined as a focal neurological deficit of less than 24 hours in duration.
Results A total of 2,226 cardiac cases were retrospectively evaluated. The frequency of stroke was 61 patients (2.7 percent). The mean age of these patients was 63.7 +/- 7.4 years, and 40 (65.6 percent) were males. Logistic EuroSCORE, left ventricular ejection fraction (as determined by two-dimensional echocardiogram) and aortic cross-clamp time were significantly correlated with postoperative neurological complications, with a p-value of less than 0.05 for all subgroups. There was a significant correlation between the presence of preoperative carotid disease (as proven by pre-and postoperative carotid ultrasonography) and postoperative neurological events (p-value equals 0.033). However, atrial fibrillation did not correlate with postoperative stroke.
Conclusion The stage of cardiac disease (risk factor level, ejection fraction and presence of carotid stenosis) correlates with stroke and may predict an adverse neurological outcome.

Keywords: cardiac disease, cardiac surgery, carotid endarterectomy, carotid stenosis, postoperative neurological complications, stroke
Singapore Med J 2009; 50(7): 674-679

Behera B, Mathur P, Das A, Kapil A
Correspondence: Dr Purva Mathur, purvamathur@yahoo.co.in

ABSTRACT
Introduction Infections caused by multidrug-resistant organisms such as extended spectrum beta-lactamase (ESBL)-producing Enterobacteriaceae have come to assume widespread proportions. Carbapenems (imipenem and meropenem) are the drugs of choice for the treatment of infections caused by ESBL-producing organisms. There is limited clinical data regarding the efficacy of the latest carbapenem, called ertapenem, against these organisms in the Indian subcontinent. In this study, ertapenem susceptibility in ESBL-producing clinical isolates was evaluated. The in vitro activities of the three carbapenems were compared in ertapenem-resistant isolates.
Methods A total of 205 ESBL-producing Enterobacteriaceae collected from inpatients and outpatients at the All India Institute of Medical Sciences, were identified and tested for antimicrobial susceptibility by the disc diffusion method and Vitek 2 advanced expert system. Ertapenem susceptibility was performed by disc diffusion and Vitek 2 in all the isolates and by E-test in 100 isolates.
Results 191 (93 percent) of the ESBL-producing isolates tested were susceptible to ertapenem. All ertapenem-susceptible isolates were also susceptible to imipenem and meropenem. Isolates with low-level ertapenem resistance retained their susceptibility to imipenem and meropenem, whereas those with high-level ertapenem resistance were resistant to both imipenem and meropenem.
Conclusion Our results suggest that ertapenem may be a viable alternative to other carbapenems for the treatment of infections caused by ESBL-producing clinical isolates. Clinical outcome studies are required to determine if ertapenem is effective for the treatment of infections caused by these organisms.

Keywords: Enterobacteriaceae, ertapenem, extended spectrum ß-lactamase, multidrug-resistant organisms
Singapore Med J 2009; 50(6): 628-632

Jain A, Agrawal BK, Varma M, Jadhav AA
Correspondence: Mrs Anuradha Jain, anushokjain@yahoo.co.in

ABSTRACT
Introduction The present study was conducted to assess the association between smoking, dietary intake of antioxidants and plasma indices of oxidative stress and antioxidant defences in male smokers (cigarette and bidi smokers).
Methods The study sample consisted of 100 healthy men, including 50 non-smokers and 50 smokers, who were subclassified into 25 cigarette smokers and 25 bidi smokers, aged 18–55 years. Erythrocyte superoxide dismutase and plasma ascorbic acid were measured as antioxidants and erythrocyte malondialdehyde as an oxidative stress index, by colorimetric methods.
Results Smokers ate less fruits and vegetables than non-smokers, leading to them having a lower antioxidant level. Erythrocyte superoxide dismutase was significantly lower in cigarette smokers (0.193 U/mgP, p-value is less than 0.05) and bidi smokers (0.169 U/mgP, p-value is less than 0.001) as compared to non-smokers (0.231 U/mgP). Plasma ascorbic acid was also significantly lower in cigarette smokers (1.45 mg/100ml, p-value is less than 0.05) as well as in bidi smokers (1.38 mg/100ml, p-value is less than 0.001) as compared to non-smokers (1.73 mg/100ml). There was a significant increase in erythrocyte malondialdehyde concentration levels in cigarette smokers (171.47 µmol/gHb, p-value is less than 0.05) as well as in bidi smokers (231.04 µmol/gHb, p-value is less than 0.001) as compared to non-smokers (127.30 µmol/gHb).
Conclusion These results provide enough evidence of increased oxidative stress and a compromised antioxidant defence system in smokers, and they are more profound in bidi smokers than in those smoking cigarettes. This study also revealed that the diet and nutrient intake of smokers are different from that of non-smokers.

Keywords: antioxidants, ascorbic acid, bidi smokers, cigarette smokers, erythrocyte malondialdehyde, oxidative stress, superoxide dismutase
Singapore Med J 2009; 50(6): 624-627

Chong VH
Correspondence: Dr Chong Vui Heng, chongvuih@yahoo.co.uk

ABSTRACT
Introduction Fasting during the month of Ramadan is one of the five holy pillars in the Islamic faith and is an obligation for all its followers. Prolonged fasting may precipitate or exacerbate gastrointestinal (GI) complaints. This study assessed the impact of Ramadan on referrals for upper GI endoscopy in a tertiary referral centre.
Methods 1,661 patients referred to the centre a month before, during and a month after the month of Ramadan over a four-year period (2004–07) were retrospectively studied. Significant endoscopic findings were taken as any bleeding lesions, severe or complicated oesophagitis, peptic ulcer disease, portal hypertension related pathologies and malignancies.
Results Overall, there was significantly less workload generated during the fasting month (397 patients, 5.7 +/- 2.7 cases per list) compared to before (603 patients, 6.9 +/- 3.0 cases per list, p-value is equal to 0.036) and after (661 patients, 7.8 +/- 3.4 cases per list, p-value is less than 0.001) the fasting month. There was no significant difference between the period before and after the fasting month (p-value equal to 0.124). There were no significant differences in the mean age and gender of the patients. During the fasting month, there were differences in the ethnicity (fewer Malays and more Chinese, p-value is equal to 0.002) and referral sources (more wards and fewer clinics, p-value is less than 0.001). There were no differences in the referral indications, oesophageal and gastric findings, but there was a significant difference in the duodenal findings (p-value is equal to 0.001), especially ulcer disease, during the fasting month.
Conclusion This study showed that significantly less workload was generated during the fasting month of Ramadan compared to the non-fasting months. There were also some differences in the referral sources, ethnicity and the endoscopic findings.

Keywords: endoscopy referrals, fasting, gastrointestinal bleeding, Ramadan
Singapore Med J 2009; 50(6): 619-623

Emam AA, Gad AM, Ahmed MM, Assal HS, Mousa SG
Correspondence: Dr Ahmed Alsayed Emam, ahmedemam6@hotmail.com

ABSTRACT
Introduction Patients with diabetic neuropathy have an imbalance, which comes with a higher risk of falls. The aim of this study was to assess posture stability using computerised dynamic posturography in type 2 diabetics mellitus patients with neuropathy as well as its relation to glycaemic control.
Methods 54 type 2 diabetics mellitus patients with peripheral neuropathy were recruited, together with 18 type 2 diabetics mellitus patients without peripheral neuropathy acting as the control group. The first group was divided into two subgroups according to glycaemic control assessed by HbA1c (A1c), the first subgroup comprising 24 patients had good glycaemic control with A1c less than or equal to seven percent and the second subgroup with 30 patients had poor glycaemic control with A1c more than 7 percent. The postural stability was evaluated using dynamic posturography.
Results The composite equilibrium score, sensory organisation test 1, 2 and 3 conditions were significantly lower in the neuropathic group as compared to the non-neuropathic group (p-value is less than 0.001). A1c was significantly correlated with the composite equilibrium score in the neuropathic group with poor glycaemic control (r-value equal to -0.395) but not correlated in the neuropathic group with good glycaemic control ( r-value equal to 0.151).
Conclusion Posture instability in type 2 diabetic patients with peripheral neuropathy reflects an impairment of the somatosensory system; also, poor glycaemic control resulted in more posture instability. The early detection of imbalance using dynamic posturography and achieving good glycaemic control may be of great help in the prevention of falls in such patients.

Keywords: glycaemic control, computerised dynamic posturography, diabetes mellitus, glycaemic control, peripheral neuropathy, type 2 diabetes mellitus
Singapore Med J 2009; 50(6): 614-618

Khadem-Ansari MH, Rasmi Y, Rahimi-Pour A, Jafarzadeh M
Correspondence: Dr Yousef Rasmi, rasmiy@umsu.ac.ir

ABSTRACT
Introduction The aim of this study was to investigate the relationship between serum apolipoprotein A-I (apoA-I) and apolipoprotein B (apoB) and the severity of coronary artery stenosis.
Methods This case-control study was carried out on 106 patients who underwent angiography and 100 healthy controls. ApoA-I and apoB as well as the serum total cholesterol, high-density lipoprotein cholesterol (HDL-C), triglyceride and low-density lipoprotein cholesterol (LDL-C) levels were measured. Very low-density lipoprotein cholesterol levels and the LDL-C/HDL-C ratio were calculated.
Results In an Iranian population with coronary artery disease (79 men and 27 women, aged 53 +/- 8.5 years), the increased levels of apoA-I and apoB were correlated with the number of involved vessels and the severity of coronary lesions. However, no significant correlation was found between the serum values of lipids as well as other lipoproteins and the number of vessels involved and the severity of coronary lesions.
Conclusion ApoA-I and apoB are indicated as risk factors for cardiovascular and, possibly, cerebrovascular diseases. From this study, it may be concluded that apoA-I and apoB serum concentration levels are independent risk factors for coronary atherosclerosis in the Iranian population. It also demonstrates a direct relationship between the severity of coronary atherosclerosis and the number of lesions in the involved vessels. It can be regarded as an index for the relationship of apoA-I and apoB to the early, still clinically asymptomatic, steps of the pathogenesis of coronary disease.

Keywords: apolipoprotein, cardiovascular disease, coronary artery disease, coronary artery stenosis
Singapore Med J 2009; 50(6): 610-613

Abdullah WZ, Idris SZ, Bashkar S, Hassan R
Correspondence: Dr Wan Zaidah Abdullah, wzaidah@kb.usm.my

ABSTRACT
Introduction The fibrinolytic system plays an important role in normal haemostasis and endothelial function. This study was conducted to compare three fibrinolytic markers, i.e. plasminogen, tissue-plasminogen activator (t-PA) and plasminogen activator inhibitor type-1 (PAI-1) between acute stroke and stable non-stroke patients and to investigate the clinical significance of these markers.
Methods A prospective study was done for a one-year period upon obtaining ethical approval from the local institution. 106 non-stroke individuals from general outpatient clinics (control group) and 51 acute stroke patients were selected. All subjects were tested for t-PA and PAI-1 levels using the enzyme immunoassay technique (Biopool TintElize®) and for plasminogen level by colorimetric assay (HemosILTM). They were followed up over a period of three months for survival and neurological recovery.
Results Only the mean t-PA level was significantly higher in acute stroke patients compared to the control group, including after adjusting for confounders (using ANCOVA). There was no statistical association between the three fibrinolytic markers and the age, gender, stroke subtypes, number of risk factors, functional impairment, survival and neurological recovery. We observed that all the eight patients who died within one month of stroke onset had high levels of t-PA. An association between high t-PA antigen and acute stroke was found during a cerebrovascular event with a 4.6-fold odds ratio compared to non-stroke controls.
Conclusion High t-PA antigen in acute stroke patients probably indicates a poor prognosis. Its value as a marker for monitoring and prognostication needs to be evaluated as a routine clinical practice.

Keywords: acute stroke, plasminogen, plasminogen activator inhibitor-1 (PAI-1), tissue plasminogen activator (t-PA)
Singapore Med J 2009; 50(6): 604-609

Agarwal R, Aggarwal AN, Gupta D
Correspondence: Dr Ritesh Agarwal, riteshpgi@gmail.com

ABSTRACT
Introduction Noninvasive ventilation (NIV) with continuous positive airway pressure (CPAP) has been shown to decrease endotracheal intubation and mortality in patients with acute cardiogenic pulmonary oedema (ACPE). The Three Interventions in Cardiogenic Pulmonary Oedema showed no advantage of NIV over standard medical therapy. This meta-analysis is an update on the efficacy and safety of two different forms of NIV (noninvasive pressure support ventilation [NIPSV] vs. CPAP) in patients with ACPE.
Methods We searched the MEDLINE and EMBASE databases for randomised clinical trials published from 1980 to 2008 that have compared NIPSV and CPAP in patients with ACPE. We calculated the odds ratio (OR) with 95 percent confidence intervals (CI) and pooled the results using three different statistical models (fixed effects, random effects and exact method).
Results Ten studies (577 and 576 in the CPAP and NIPSV groups, respectively) met our inclusion criteria. NIPSV performed similar to CPAP in decreasing the intubation rates (OR 0.8; 95 percent CI 0.43–1.49), hospital mortality (OR 1.08; 95 percent CI 0.76–1.54) and the occurrence of myocardial infarction (OR 0.8; 95 percent CI 0.36–1.76). The results were similar when pooling the data with any of the three statistical methods and stratifying for the type of pressure therapy (fixed vs. variable) except for myocardial infarction, which was more frequent in the fixed pressure NIPSV arm (OR 5.06; 95 percent CI 1.66–15.44).
Conclusion NIPSV appears to be as safe and efficacious as CPAP, if titrated rather than fixed pressures are employed.

Keywords: acute cardiogenic pulmonary oedema, continuous positive airway pressure, intratracheal intubation, noninvasive pressure support ventilation, noninvasive ventilation, pulmonary oedema, positive-pressure respiration, respiratory insufficiency
Singapore Med J 2009; 50(6): 595-603

Tan KK, Nalachandran S, Chia KH
Correspondence: Dr Ker-Kan Tan, kerkan@gmail.com

ABSTRACT
Introduction Endovenous lasertherapy (EVLT) is one of the many minimally-invasive procedures that have been developed in recent years for the treatment of varicose veins. We present our single centre experience of 169 patients who underwent EVLT.
Methods All patients who underwent EVLT since its introduction in our institution were included in our series.
Results A total of 270 incompetent long saphenous veins in 169 patients were ablated by EVLT from February 2006 to January 2008. Bilateral EVLT was performed in 101 (59.8 percent) patients, with the remaining 68 (40.2 percent) undergoing unilateral EVLT. The mean age of the patients was 54 (range 19–78) years and there were 112 (66.3 percent) women. The majority of our patients (63.3 percent) had symptoms for more than five years. The symptoms included lower limb cramps and aches (47.9 percent) as well as lower limb swelling (16.6 percent). The median follow-up was six months. Complications from our series included numbness over the affected lower limbs (10.7 percent) and skin pigmentation (4.1 percent). Only 2.4 percent of patients had recurrence after one year.
Conclusion Early results with EVLT have been impressive, and this study has reaffirmed the safety and effectiveness of EVLT in the treatment of varicose veins.

Keywords: endovenous laser therapy, long saphenous veins, varicose veins
Singapore Med J 2009; 50(6): 591-594