High-grade culprit lesions are a common cause of ST-segment elevation myocardial infarction

INTRODUCTION

Conventional knowledge holds that the majority of ruptured atherosclerotic plaques causing ST-segment elevation myocardial infarction (STEMI) are found in moderate stenoses that produce < 50% loss of arterial diameter. This study aimed to analyse the culprit lesions in patients who presented with STEMI and underwent primary percutaneous coronary intervention (PPCI) at our institution.

METHODS

Patients who underwent PPCI between June 2008 and August 2010 at our institution were included in the analysis. Quantitative coronary angiography was performed for the culprit lesions immediately after antegrade flow was restored by thrombectomy, low-profile balloon predilatation or guidewire crossing.

RESULTS

A total of 1,021 patients were included in the study. The mean age was 57 ± 12 years and 85.2% were male. Lesion measurement was done after coronary flow was restored by thrombectomy (73.1%), balloon dilatation (24.1%) and following guidewire passage across the lesion (2.8%). Mean minimal luminal diameter was 1.1 ± 0.5 mm, mean reference vessel diameter was 2.8 ± 0.6 mm, mean diameter stenosis was 61 ± 16% and mean lesion length was 16 ± 6 mm. Most (80.2%) of the culprit lesions had diameter stenoses > 50% (p < 0.01). Although balloon angioplasty was performed in 24.1% of the patients, the majority (64.2%) still had diameter stenoses > 50%. High-grade stenoses (> 50%) were more frequently observed in male patients (p = 0.04).

CONCLUSION

Contrary to the existing paradigm, we found that most of the patients with STEMI in our institution had culprit lesions with diameter stenosis > 50%.     

Improvement in left ventricular function assessed by tissue Doppler imaging after aortic valve replacement for severe aortic stenosis

INTRODUCTION

The effects of reduction of left ventricular (LV) systemic afterload following aortic valve replacement (AVR) for severe aortic valve stenosis (AS) were investigated, using echocardiography and tissue Doppler imaging (TDI).

METHODS

We compared the preoperative and postoperative echocardiographic assessments of 23 patients with severe AS who had undergone isolated AVR (n = 13) or concomitant AVR with coronary artery bypass grafting (CABG) (n = 10). Conventional echocardiographic evaluations and TDI at the lateral mitral annulus were performed.

RESULTS

Echocardiography was performed at a median of 120 (interquartile range: 66–141) days after AVR. There was significant reduction in aortic transvalvular mean pressure gradient after AVR. Although LV dimensions, mass and ejection fraction remained unchanged, LV diastolic and systolic functions improved (as observed on TDI). Early diastolic (E’), late diastolic (A’) and systolic (S’) mitral annular velocities increased significantly (p < 0.05). There was significant improvement in TDI-derived parameters among the patients who had isolated AVR, while among the patients who had concomitant AVR with CABG, only S’ had significant improvement (p = 0.028).

CONCLUSION

TDI was able to detect improvements in LV systolic and diastolic function after AVR for severe AS. There was less improvement in the TDI-derived diastolic parameters among patients who underwent concomitant AVR with CABG than among patients who underwent isolated AVR.     

Distribution of branchial anomalies in a paediatric Asian population

INTRODUCTION

The objective of the present study was to review the distribution and incidence of branchial anomalies in an Asian paediatric population and highlight the challenges involved in the diagnosis of branchial anomalies.

METHODS

This was a retrospective chart review of all paediatric patients who underwent surgery for branchial anomalies in a tertiary paediatric hospital from August 2007 to November 2012. The clinical notes were correlated with preoperative radiological investigations, intraoperative findings and histology results. Branchial anomalies were classified based on the results of the review.

RESULTS

A total of 28 children underwent surgery for 30 branchial anomalies during the review period. Two children had bilateral branchial anomalies requiring excision. Of the 30 branchial anomalies, 7 (23.3%) were first branchial anomalies, 5 (16.7%) were second branchial anomalies, 3 (10.0%) were third branchial anomalies, and 4 (13.3%) were fourth branchial anomalies (one of the four patients with fourth branchial anomalies had bilateral branchial anomalies). In addition, seven children had 8 (26.7%) branchial anomalies that were thought to originate from the pyriform sinus; however, we were unable to determine if these anomalies were from the third or fourth branchial arches. There was inadequate information on the remaining 3 (10.0%) branchial anomalies for classification.

CONCLUSION

The incidence of second branchial anomalies appears to be lower in our Asian paediatric population, while that of third and fourth branchial anomalies was higher. Knowledge of embryology and the related anatomy of the branchial apparatus is crucial in the identification of the type of branchial anomaly.     

Syndecan-1 is a potential biomarker for triple-positive breast carcinomas in Asian women with correlation to survival

INTRODUCTION

While overexpression of syndecan-1 has been associated with aggressive breast cancer in the Caucasian population, the expression pattern of syndecan-1 in Asian women remains unclear. Triple-positive breast carcinoma, in particular, is a unique subtype that has not been extensively studied. We aimed to evaluate the role of syndecan-1 as a potential biomarker and prognostic factor for triple-positive breast carcinoma in Asian women.

METHODS

Using immunohistochemistry, staining scores of 61 triple-positive breast carcinoma specimens were correlated with patients’ clinicopathological variables such as age, ethnicity, tumour size, histological grade, lymph node status, lymphovascular invasion, associated ductal carcinoma in situ grade, recurrence and overall survival.

RESULTS

Syndecan-1 had intense staining scores in triple-positive invasive ductal breast carcinomas when compared to normal breast tissue. On multivariate analysis, syndecan-1 epithelial total percentage and immunoreactivity score showed statistical correlation with survival (p = 0.02).

CONCLUSION

The intense staining scores of syndecan-1 and their correlation with overall survival in patients with triple-positive breast carcinoma suggest that syndecan-1 may have a role as a biological and prognostic marker in patients with this specific subtype of breast cancer.     

The Little India riot: experience of an emergency department in Singapore

INTRODUCTION

Singapore experienced its second riot in 40 years on 8 December 2013, in the area known as Little India. A retrospective review of 36 casualties treated at the emergency department was conducted to evaluate injury patterns.

METHODS

Characteristics including the rate of arrival, injury severity, type and location, and disposition of the casualties were analysed.

RESULTS

The injuries were predominantly mild (97.2%), with the most common injuries involving the head (50.0%) and limbs (38.9%). 97.2% of the casualties were managed as outpatient cases.

CONCLUSION

The majority of the injuries in this incident were mild and could be managed as outpatient cases. Important lessons were learnt from the incident about the utilisation of manpower and safety of staff in the emergency department.     

Review of sleep studies of patients with chronic insomnia at a sleep disorder unit

INTRODUCTION

Chronic insomnia is associated with many physical and psychiatric illnesses, and its underlying aetiology needs to be identified in order to achieve safe and effective treatment. Obstructive sleep apnoea (OSA) and periodic limb movement disorder (PLMD) are common primary sleep disorders that can lead to chronic insomnia. Patients with these conditions are evaluated using polysomnography (PSG).

METHODS

The PSG records of 106 patients with chronic insomnia who presented to a multidisciplinary sleep clinic in Singapore over a five-year period were reviewed. To examine the utility of PSG in the evaluation of chronic insomnia, the clinical diagnoses of the patients before and after the sleep studies were compared.

RESULTS

Among the 106 patients, 69 (65.4%) were suspected to have primary sleep disorders based on clinical history and examination alone. Following PSG evaluation, 42.5% and 4.7% of the study population were diagnosed with OSA and PLMD, respectively. OSA was found in 35.9% of the 39 patients who had underlying psychiatric conditions.

CONCLUSION

This study illustrates that many patients with chronic insomnia have underlying primary sleep disorders. It also highlights the danger of attributing chronic insomnia in psychiatric patients to their illness, without giving due consideration to other possible aetiologies. Clinicians should maintain a high index of suspicion for the presence of other aetiologies, and make timely and targeted referrals for sleep studies where appropriate.     

Cemented hemiarthroplasty in traumatic displaced femoral neck fractures and deep vein thrombosis: is there really a link?

INTRODUCTION

Traumatic displaced femoral neck fractures in the elderly can be treated with cemented or uncemented hemiarthroplasty with good outcomes. Earlier studies reported a higher incidence of deep vein thrombosis (DVT) associated with cemented prostheses in elective total hip or knee arthroplasty. In addition, the hypercoagulable state after a traumatic femoral neck fracture and possible thrombogenic properties of bone cement could put these patients at greater risk for thromboembolism. We aimed to compare the incidence of DVT and progression to pulmonary embolism (PE) or mortality in cemented and uncemented hemiarthroplasty.

METHODS

The data of 271 patients treated with cemented or uncemented hemiarthroplasty after a traumatic displaced femoral neck fracture was retrospectively analysed for the incidence of DVT. The level of thrombosis, progression to PE and mortality were compared.

RESULTS

There were 133 (49.1%) patients with cemented hemiarthroplasty, while 138 (50.9%) had uncemented hemiarthroplasty. The patients had an average age of 76.6 (range 53–99) years and 11 (4.1%) patients had DVT. There were no significant differences in development of DVT, level of thrombosis, PE and mortality regardless of whether a cemented or an uncemented prosthesis was used.

CONCLUSION

Cemented hemiarthroplasty is not associated with higher risks of DVT, PE or mortality in patients with traumatic displaced femoral neck fracture. Cemented prostheses can be safely used for this group of patients.     

A review of oral food challenges in children presenting to a single tertiary centre with perceived or true food allergies

INTRODUCTION

The prevalence of perceived food allergies exceeds that of true food allergies. Unnecessary food avoidance may increase parental and patient anxiety, reduce quality of life and increase the risk of nutritional deficiency. An oral food challenge (OFC) can provide an objective measure regarding the presence or absence of food allergies in a child. This study reviews the indications for and outcomes of OFCs performed on children.

METHODS

A retrospective review was performed on all children who underwent OFCs at the Allergy Unit of the National University Hospital, Singapore, over a three-year period.

RESULTS

A total of 197 OFCs were performed among 58 patients (34 male, 24 female). Most of the tests were for allergies to tree nuts (n = 107). Among the OFCs, 43.1% were for foods that were avoided and never eaten due to perceived food allergies, 25.9% were for foods that had previously resulted in positive skin prick tests (SPTs) and/or immunoassay results, 16.2% were for foods thought to worsen eczema and 14.7% were for foods thought to have caused a previous reaction. Of all the OFCs, 5% were positive, although adverse reactions were mostly cutaneous. Challenge-positive patients had either positive SPTs (wheal > 3 mm) or raised serum immunoglobulin E levels to specific foods that they reacted to during the challenges. No episodes of anaphylaxis were reported after the challenge. Most of the patients were able to safely introduce the avoided foods into their diets.

CONCLUSION

OFCs provide an objective assessment for suspected food allergies.     

Tuberculosis trends over a five-year period at a tertiary care university-affiliated hospital in Singapore

INTRODUCTION

Tuberculosis (TB), a potentially fatal infectious disease, poses significant health problems. The objective of this study was to analyse trends among newly diagnosed TB patients seen at the Singapore General Hospital (SGH).

METHODS

This study was a retrospective case record review of notified TB patients at SGH between 2006 and 2010 (inclusive).

RESULTS

A total of 1,979 cases of TB were notified over the five years. The number increased from 368 in 2006 to 407 in 2010 (p = 0.51), in tandem with the increasing number of patients seen at the hospital and the rising population in Singapore. Singaporean residents accounted for 82.8% of the cases, while non-Singaporean residents and non-residents made up the remainder. The year-to-year percentage of non-Singaporean residents and non-residents notified remained stable throughout the five years (p = 0.783). The number of male Singaporean residents (70.7%) notified was more than twice that of female Singaporean residents (29.3%). The majority of patients infected with TB (31.9%) were elderly patients aged > 65 years. Although testing for the human immunodeficiency virus increased from 43.8% (2006) to 64.2% (2010), the number detected with coinfection remained stable (14 and 12 patients in 2006 and 2010, respectively). Mortality rates also remained stable at 12.0%.

CONCLUSION

We cannot afford complacency, as there was no downward trend in the number of notified TB cases at SGH from 2006 to 2010. As the elderly contribute significantly to the TB burden, increased efforts are required to manage this vulnerable population.     

Clinical characteristics,outcome and early induction deaths in patients with acute promyelocytic leukaemia: a five-year experience at a tertiary care centre

INTRODUCTION

Acute promyelocytic leukaemia (APL) is a distinct clinical and biological subtype of acute myeloid leukaemia. APL is notorious for causing early death during induction therapy, resulting in induction failure. The aim of our study was to report the clinical characteristics, outcome and early induction deaths with regard to patients with APL seen at our hospital.

METHODS

This was a retrospective study carried out at Aga Khan University Hospital, Karachi, Pakistan. Patients aged > 15 years diagnosed with APL within the period September 2007–September 2012 were included in the study.

RESULTS

Within the study period, 26 patients were diagnosed with APL based on morphology and the detection of t(15;17)(q24.1;q21.1) and promyelocytic leukaemia-retinoic acid receptor alpha (PML-RARA). The male to female ratio was 1:1. The median age of the patients was 41 (range 16–72) years. In all, there were 13 (50.0%) high-risk patients, and early induction death rate was 61.5%. Causes of early induction deaths (n = 16) included haemorrhage in 7 (43.8%) patients, differentiation (ATRA) syndrome in 7 (43.8%) and infection in 2 (12.5%). The survival rate among patients who survived the early period was 70% at 42 months. The relapse rate was 30%.

CONCLUSION

Early induction death rate was very high in patients with APL. The most common cause of early induction death in our study was haemorrhage. Outcome among patients with APL was found to be better among those who survived the initial period.     

Paediatric palliative care at home: a single centre’s experience

INTRODUCTION

There is increased awareness of paediatric palliative care in Malaysia, but no local published data on home care services. We aimed to describe the paediatric experience at Hospis Malaysia, a community-based palliative care provider in Malaysia.

METHODS

We conducted a retrospective case note review of patients aged up to 21 years who were referred to Hospis Malaysia from 2009 to 2013.

RESULTS

A total of 137 patients (92 male, 45 female) with a median age of 140 (3–250) months were included in this study. The majority (71.5%) had malignancies. At referral, 62 patients were still in hospital and 17 died prior to discharge. A total of 108 patients received home visits. At the first home visit, 89.8% of patients had at least one physical symptom. Pain was the most common (52.5%) symptom. Patients had various supportive devices: 39 were on feeding tubes, ten had tracheostomies, five were on bilevel positive airway pressure and ten had urinary catheters. 66 families discussed the preferred location of care at end-of-life. Among those who died, 78.9% died at home, as they preferred (p < 0.001). Regression analysis showed no statistically significant association between a home death and age, diagnosis and number of home visits. Bereavement follow-up occurred for 93.3% of families.

CONCLUSION

Community care referrals tend to occur late, with 25.5% of patients dying within two weeks of referral. At referral, patients often had untreated physical symptoms. The majority of families preferred and had a home death.     

Incidence of discontinuation of angiotensin-converting enzyme inhibitors due to cough,in a primary healthcare centre in Singapore

INTRODUCTION

The incidence of cough induced by angiotensin-converting enzyme (ACE) inhibitors has been reported to be 5%–20%, with less than half of affected patients requiring discontinuation due to persistent cough. However, the incidence in the local Asian population has not been studied. This study aimed to objectively evaluate the incidence of discontinuation of ACE inhibitors due to cough, in a primary healthcare centre in Singapore.

METHODS

We retrospectively reviewed the medical records, both electronic and written, of patients who attended Tampines Polyclinic to identify those who were newly prescribed ACE inhibitors. The written medical records were analysed to identify patients who discontinued the use of ACE inhibitors and to find out the reasons for discontinuation.

RESULTS

A total of 424 patients were identified during the study period. Out of the 424 patients, 129 (30.4%) discontinued the use of ACE inhibitors due to cough. Overall, 90 (21.2%) patients who were initially started on ACE inhibitors were eventually switched to angiotensin receptor blockers (ARBs).

CONCLUSION

In our cohort, the incidence of discontinuation of ACE inhibitors due to cough is higher than most other studies. The relationship between ethnicity and tolerance of medications should not be underestimated. As there is a high incidence of discontinuation of ACE inhibitors due to cough in the local population, ARBs may be a reasonable substitute as a first-line medication, if clinically indicated.     

A review of perioperative anaphylaxis at a Singapore tertiary hospital

INTRODUCTION

Perioperative anaphylaxis is an anaesthetic emergency, but its incidence is not well described in the local literature. This retrospective study aims to look at a group of patients who had perioperative anaphylaxis in our institution.

METHODS

We conducted a retrospective review of electronic databases and clinical case sheets, and identified 34 patients who had possible perioperative anaphylaxis during anaesthesia in our institution between 1 January 2007 and 30 April 2012.

RESULTS

After reviewing clinical and biochemical data, we found that 16 out of 151,876 patients who underwent surgery had confirmed perioperative anaphylaxis, an incidence of 1:10,000. Neuromuscular blockers were identified as the most common causative agent for perioperative anaphylaxis. The offending agent could not be identified in seven patients.

CONCLUSION

To the best of our knowledge, this is the first study in Southeast Asia on the incidence of perioperative anaphylaxis. Having a preoperative history of allergy did not seem to predispose patients to the subsequent development of perioperative anaphylaxis.     

Optimal head rotation and puncture site for internal jugular vein cannulation after laryngeal mask airway insertion

INTRODUCTION

We studied the effect of head rotation on the relative position of the right common carotid artery (CCA) and the right internal jugular vein (IJV) in patients with laryngeal mask airway (LMA) insertion to evaluate the accuracy of anatomical landmarks for right IJV cannulation.

METHODS

We simulated needle insertion to the right IJV on sonograms via the central landmark approach and an approach using the external jugular vein, in patients with LMA insertion (n = 50) or endotracheal intubation (E-tube, n = 50). Overlap index and successful simulation rates were measured according to the different degrees of head rotation.

RESULTS

The overlap index between the right CCA and the right IJV increased with greater degrees of head rotation. It was significantly greater in the LMA insertion group than in the E-tube group in the following head rotation positions: neutral, 15° and 45°. The success rate of the simulation was lower in the LMA insertion group than in the E-tube group. In the LMA insertion group, the success rate of the simulation was highest (62%) with the central landmark approach and in the 15° head rotation position.

CONCLUSION

In the LMA insertion group, the overlap index increased incrementally with greater head rotation degrees (from neutral to 45°). The central landmark approach and 15° head rotation position appear to be the optimal puncture site and degree of head rotation for right IJV cannulation in patients with LMA insertion.     

A prospective study of epidemiological risk factors for ingestion of fish bones in Singapore

INTRODUCTION

Ingestion of fish bones is a common clinical complaint among adult patients. The aim of this study was to evaluate the epidemiological and behavioural risk factors for fish bone ingestion.

METHODS

Between 2009 and 2010, a physician-administered questionnaire was administered to 112 consecutive patients who presented to the emergency department of an adult tertiary hospital with the complaint of fish bone ingestion.

RESULTS

The wearing of dentures, the use of utensils to eat fish and the practice of deboning fish in one’s mouth were found to be associated with an increased risk of fish bone ingestion.

CONCLUSION

To prevent the occurrence of fish bone ingestion and its possible complications, at-risk populations should be advised on the precautions to take when eating boned fish.     

Inappropriate use of proton pump inhibitors in a local setting

INTRODUCTION

There are growing concerns that the use of proton pump inhibitors (PPIs) may be inappropriate in instances that do not conform to evidence-based indications. This point-prevalence study aimed to investigate the frequency, indications and appropriateness of use of PPIs in hospitalised patients on a randomly chosen day.

METHODS

On a randomly chosen day, all inpatients were documented, and those on any form of PPIs on that day were determined. Indications for maintaining these patients on PPIs were obtained from the electronic medical records, which were then recorded and cross-referenced against a list of accepted indications adapted from the US Food and Drug Administration (FDA)-approved list.

RESULTS

In all, 1,025 inpatients were documented. Of the 477 (46.5%) inpatients using PPIs, only 219 (45.9%) fulfilled the FDA-approved indications, while the majority (n = 258, 54.1%) did not. Overall, PPIs were not strictly indicated for use in 206 (43.2%) inpatients, according to FDA criteria. Of the 477 inpatients on PPIs, 52 (10.9%) had borderline indications based on expert consensus/guidelines other than FDA criteria.

CONCLUSION

Although the use of PPIs is prevalent in hospitals, less than half of the hospitalised patients using PPIs in our study had evidence-based indications that supported such use. The overuse of PPIs has a negative impact on healthcare costs and may lead to adverse effects. Steps to curb the inappropriate use of PPIs should address factors such as indications for the initiation of PPIs, and reassessment of the need for ongoing PPI use in inpatients upon discharge and during outpatient reviews.     

Effectiveness of medical thoracoscopy and thoracoscopic talc poudrage in patients with exudative pleural effusion

INTRODUCTION

This study aimed to assess the effectiveness of medical thoracoscopy (MT) and thoracoscopic talc poudrage (TTP) in patients with exudative pleural effusion.

METHODS

We evaluated the diagnostic yields, complications and outcomes of MT and TTP in 41 consecutive patients with symptomatic pleural effusions who were planned to undergo both procedures from 1 December 2011 to 30 November 2012. Data was reviewed retrospectively and prospectively up to March 2013.

RESULTS

Among the 41 patients, 36 underwent MT with the intent of biopsy and talc pleurodesis, 2 underwent MT for pleurodesis only and 3 had failed MT. Aetiologies of pleural effusion included lung cancer (n = 14), tuberculosis (n = 9), breast cancer (n = 7), ovarian cancer (n = 2), malignant mesothelioma (n = 1), congestive cardiac failure (n = 1), peritoneal dialysis (n = 1) and hepatic hydrothorax (n = 1); pleural effusion was undiagnosed in five patients. The overall diagnostic yield of MT, and the yield in tubercular and malignant pleural effusions were 77.8%, 100.0% and 82.6%, respectively; it was inconclusive in 22.2%. Complications that occurred were self-limiting, with no procedure-related mortality. The 30-day mortality rate was 17.1%. A total of 15 patients underwent TTP. The 30-, 60- and 90-day success rates were 77.8%, 80.0% and 80.0%, respectively, with one patient having complications (i.e. empyema). The 30-day mortality was 40.0%.

CONCLUSION

MT is a safe procedure with high diagnostic yields in undiagnosed pleural effusions. TTP is an effective method to stop recurrence of pleural effusions.     

Cerebellar strokes: a clinical outcome review of 79 cases

INTRODUCTION

Cerebellar infarcts and haemorrhages are relatively uncommon, accounting for less than 10% of all strokes. The objective of the present study was to quantify and compare the outcomes of patients with cerebellar infarct and those of patients with cerebellar haemorrhage, as well as to identify the risk factors that predict poor outcome in patients with cerebellar stroke.

METHODS

We retrospectively reviewed the medical records of consecutive patients admitted to National University Hospital, Singapore, between 2004 and 2006, within one week of cerebellar stroke onset. Baseline data included demographics, concomitant comorbidities, and the presence or absence of brainstem compression and hydrocephalus (on computed tomography or magnetic resonance imaging). The Glasgow Outcome Scale and modified Rankin Score were used to assess outcome at discharge and at six months after discharge.

RESULTS

A total of 79 patients with cerebellar stroke were admitted during the study period. Of these 79 patients, 17.7% died and 31.6% had poor outcomes at six months after discharge. Patients with cerebellar haemorrhage were found to be more likely to have poor outcomes as compared to patients with cerebellar infarct, both at discharge (odds ratio [OR] 4.3, 95% confidence interval [CI] 1.3–14.1) and at six months after discharge (OR 5.2, 95% CI 1.6–17.2). When compared to small lesions (< 5 cm³), lesions > 20 cm³ were significantly associated with poorer outcomes and the development of hydrocephalus and brainstem compression.

CONCLUSION

Cerebellar strokes are a significant cause of morbidity and mortality. The outcomes of patients with cerebellar haemorrhage are more likely to be worse than those of patients with cerebellar infarct.