Electrocardiographic findings in pulmonary embolism

Pulmonary embolism (PE) poses a challenge to physicians, as it can be difficult to diagnose but results in significant mortality and morbidity in patients. Diagnosing PE requires an integrated approach using clinical findings, electrocardiography (ECG), blood investigations and imaging modalities. Abnormalities in ECG are common among patients with massive acute PE and can serve as a prognostic indicator. In this article, we describe the ECG presentations of two patients diagnosed with PE, and review the literature on the various types of ECG presentations and their role in predicting the prognosis of PE.     

Electrocardiographic changes in acute perimyocarditis

Pericarditis and myocarditis are characterised by electrocardiographic changes and elevated cardiac enzymes, respectively, and patients with perimyocarditis often complain of chest discomfort. These findings are nonspecific and often lead to diagnostic difficulties, as ST-elevation myocardial infarction commonly presents in a similar fashion. Clinical differentiation between perimyocarditis and myocardial infarction are especially important because adverse side effects can occur if reperfusion therapy is administered for a patient with acute pericarditis or if a diagnosis of acute myocardial infarction is missed. We herein describe a case of perimyocarditis with ST elevation and raised cardiac markers, which led to two emergency coronary angiographies that were subsequently found to be normal. We include the three serial electrocardiographies (ECGs) performed to show the characteristic features of perimyocarditis and further discuss the importance of identifying typical and atypical ECG features of pericarditis.     

Severe hypoxaemia can predict unfavourable clinical outcomes in individuals with pulmonary embolism aged over 40 years

INTRODUCTION

Acute pulmonary embolism (APE) is an urgent clinical condition that can progress in a wide variety of ways. Therefore, we sought to develop an easy-to-apply algorithm, to be based on readily available clinical indicators, effective in predicting unfavourable outcomes.

METHODS

This was a retrospective cohort study based on systematically collected data in a database. The study included 102 patients with APE who were admitted to a tertiary care hospital. The following outcomes were defined as unfavourable shock, the need for mechanical ventilation, the use of thrombolytics, and death. Logistic regression analysis was used to explore variables significantly associated with outcome and to calculate post-test probabilities.

RESULTS

The prevalence of unfavourable outcomes was 25.5% (26 of the 102 patients with APE). The risk of an unfavourable outcome was reduced to 7.0% for patients with APE who were aged ≤ 40 years. In patients with APE who were aged > 40 years, the presence of hypoxaemia (i.e. peripheral oxygen saturation < 90%) alone increased the risk of an unfavourable outcome to 57.0%. A recent history of trauma and the presence of pre-existing lung or heart disease were significantly associated with unfavourable outcomes. The inclusion of those variables in the logistic regression model increased the post-test risk of an unfavourable outcome to 65.0%–86.0%.

CONCLUSION

Advanced age (i.e. > 40 years), the presence of hypoxaemia, a recent history of trauma and the presence of pre-existing lung or heart disease are risk factors for unfavourable outcome in patients with APE.     

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%.     

Recurrent myocardial infarction secondary to Prinzmetal’s variant angina

Prinzmetal’s variant angina describes chest pain secondary to reversible coronary artery vasospasm in the context of both diseased and non-diseased coronary arteries. Symptoms typically occur when the patient is at rest and are associated with transient ST-segment elevation. Acute episodes respond to glyceryl trinitrate, but myocardial infarction and other potentially fatal complications can occur, and long-term management can be challenging. Although it is not well understood, the underlying mechanism appears to involve a combination of endothelial damage and vasoactive mediators. In this case, a 35-year-old woman with myocardial infarction secondary to coronary artery vasospasm experienced recurrent chest pain. Coronary angiography revealed severe focal stenosis in the mid left anterior descending artery, which completely resolved after administration of intracoronary glyceryl trinitrate. The patient was discharged on nitrates and calcium channel blockers. The patient re-presented with another myocardial infarction, requiring up-titration of medical therapy.     

Not that way: Advance Care Planning

Advance Care Planning (ACP) is a process of discussion of healthcare decisions with regard to a patient’s future health and personal care, should they become unable to make or communicate their own decisions in the future. ACP can be as simple as a chat about the patient’s end-of-life wishes with their trusted loved ones, and may involve their doctors, organisations and trained facilitators. The process can be documented with available online resources, such as structured tools. Family physicians, with whom patients share unique therapeutic relationships, are in the best position to introduce and start the ACP conversation with their patients.     

Clinics in diagnostic imaging (155). Incidental PDA with secondary pulmonary arterial hypertension.

We report the case of a 70-year-old man with an asymptomatic large patent ductus arteriosus (PDA) incidentally detected on triple-rule-out computed tomography (CT). CT clearly demonstrated a vascular structure connecting the descending thoracic aorta to the roof of the proximal left pulmonary artery, consistent with a PDA. Secondary pulmonary arterial hypertension was also evident on CT. The patient was eventually diagnosed with acute coronary syndrome and was successfully treated with coronary artery bypass graft surgery and concomitant patch closure of the PDA. This article aims to outline the imaging features of PDA and highlight the information provided by CT, which is crucial to treatment planning. The pathophysiology, clinical manifestations and closure options of PDA are also briefly discussed.     

Acute myocardial infarction and subclavian artery occlusion in a 41-year-old woman with Beh?et’s disease: coronary and large vessel arteritis

We report the case of a 41-year-old Chinese woman with Behçet’s disease (BD) complicated by acute myocardial infarction, requiring inotropic and ventilatory support. Angiography showed critical left anterior descending coronary artery stenosis, a blocked left subclavian artery and left carotid artery stenosis. The patient was successfully treated with a high dose of immunosuppressants, standard anti-ischaemic therapy and percutaneous coronary intervention. Although life-threatening, coronary arteritis is a treatable manifestation of BD. We suggest that the diagnosis of coronary arteritis be considered in patients with BD who present with chest pain. Involvement of other arteries should also be looked out for in these patients.     

Increased serum visfatin as a risk factor for atherosclerosis in patients with ischaemic cerebrovascular disease

INTRODUCTION

The present study aimed to investigate the possible associations between serum levels of visfatin, an adipokine, and atherosclerosis in patients with ischaemic cerebrovascular disease.

METHODS

A total of 95 participants were recruited for this study. Group A comprised 35 individuals with no history of cerebrovascular disease (control group) and Group B comprised 60 patients with ischaemic cerebrovascular disease. Group B was further categorised into two subgroups based on the ultrasonographic findings of the common carotid artery intima-media thickness (CCA-IMT) – Group B1 consisted of 21 patients with no atherosclerosis (i.e. CCA-IMT ≤ 0.9 mm) and Group B2 consisted of 39 patients with atherosclerosis (i.e. CCA-IMT > 0.9 mm). The body mass index, fasting blood total cholesterol, triglycerides, high-density lipoprotein cholesterol, low-density lipoprotein cholesterol and glucose levels of each patient were measured. Serum visfatin levels were determined using enzyme-linked immunosorbent assays. Visfatin levels were compared between groups, and stepwise logistic regression analysis was used to identify risk factors for atherosclerosis, including visfatin levels.

RESULTS

The mean serum visfatin level of the patients in Group B was higher than that in Group A (75.5 ± 77.80 ng/mL vs. 8.6 ± 4.69 ng/mL; p < 0.05) and the level was higher in patients from Group B2 than those from Group B1 (89.0 ± 80.68 ng/mL vs. 50.4 ± 72.44 ng/mL; p < 0.05). Multivariate regression analysis showed that CCA-IMT values were not significantly associated with visfatin levels. However, logistic regression analysis showed that serum visfatin was an independent risk factor for atherosclerosis (odds ratio 37.80; p = 0.004).

CONCLUSION

Serum visfatin may be an independent risk factor for cerebral infarction, as high serum visfatin levels are positively associated with the underlying pathogenic mechanisms of ischaemic cerebrovascular disease.     

Imaging of the spleen: what the clinician needs to know

The spleen is considered ‘the forgotten organ’ among radiologists and clinicians, although it is well visualised on abdominal computed tomography and magnetic resonance imaging. Moreover, the spleen is commonly involved in a wide range of pathologic disorders. These include congenital anomalies, infectious and inflammatory diseases, vascular disorders, benign and malignant tumours, and systemic disorders. In this review, we focus on the key imaging findings of the normal spleen, its variants, as well as relevant congenital and acquired abnormalities. It is of utmost importance to recognise and correctly interpret the variable spectrum of abnormalities that may involve the spleen, in order to avoid unnecessary invasive procedures and to guide adequate treatment.     

Multiple oesophago-respiratory fistulae: sequelae of pulmonary tuberculosis in retroviral infection

Pulmonary tuberculosis (PTB) is a common infectious disease worldwide. However, mediastinal tuberculous lymphadenitis complicated by oesophageal involvement and oesophago-respiratory fistula is now uncommon due to improved anti-tuberculous regimes and better general awareness. The overall incidence of acquired oesophago-respiratory fistula due to infection is low, and therefore, the lesion is not often a frontrunner in differential diagnosis. Still, tuberculous oesophago-respiratory fistulae can potentially occur in patients with retroviral disease, as they tend to have atypical and more virulent manifestations. In this study, we report the case of multiple oesophago-respiratory fistulae in a patient with PTB and retroviral disease, and highlight the computed tomography features of these lesions as an atypical presentation of PTB in retroviral disease. Clinicians should suspect oesophago-respiratory fistulae if patients present with Ono’s sign, and remain particularly vigilant for patients with underlying PTB and retroviral disease, as early diagnosis and treatment could help to reduce mortality.     

Sleep-related breathing disorder is associated with hyperactivity in preschoolers

INTRODUCTION

Sleep problems are a prominent feature in children with attention deficit hyperactivity disorder (ADHD). Unlike existing studies that focused on extreme samples (i.e. normal vs. ADHD), our study investigated the associations of sleep-related behaviours and ADHD features in nonclinical Chinese preschoolers.

METHODS

All participants were recruited via advertisements and screened for eligibility through a telephone interview prior to an onsite visit. The maternal reports of the Conners’ Parent Rating Scale (CPRS) and Pediatric Sleep Questionnaire (PSQ) were acquired from 110 Chinese preschoolers aged six years. Regression models were used to examine the association between CPRS and PSQ scores.

RESULTS

The results obtained from regression models on the CPRS and PSQ scores of the 110 participants showed that none of the sleep-related behavioural measures (i.e. sleep-related breathing disorder [SRBD], snoring, daytime sleepiness, restless legs syndrome) was associated with inattention in our sample. However, worse SRBD was associated with higher hyperactivity.

CONCLUSION

Our study underpins the importance of understanding the relationship between sleep-related behaviours and ADHD characteristics before the usual age of clinical diagnosis in children with ADHD.     

Relationship between pulmonary function and degree of spinal deformity,location of apical vertebrae and age among adolescent idiopathic scoliosis patients

INTRODUCTION

This retrospective review aimed to examine the relationship between preoperative pulmonary function and the Cobb angle, location of apical vertebrae and age in adolescent idiopathic scoliosis (AIS). To our knowledge, there have been no detailed analyses of preoperative pulmonary function in relation to these three factors in AIS.

METHODS

A total of 38 patients with thoracic or thoracolumbar scoliosis were included. Curvature of spinal deformity was measured using the Cobb method. Forced vital capacity (FVC) and forced expiratory volume in one second (FEV1) were used to evaluate preoperative pulmonary function. Statistical methods were used to analyse the relationship between preoperative pulmonary function and the factors that may contribute to poor pulmonary function.

RESULTS

The mean age of the patients was 16.68 ± 6.04 years. An inverse relationship was found between the degree of the Cobb angle and FVC as well as FEV1; however, the relationships were not statistically significant (p = 0.057 and p = 0.072, respectively). There was also a trend towards a significant negative correlation between the thoracic curve and FVC (p = 0.014). Patients with larger thoracic curves had lower pulmonary function. A one-year increase in age significantly decreased FVC by 1.092 units (p = 0.044). No significant relationship between age and preoperative FEV1 was found. The median FVC was significantly higher in patients with affected apical vertebrae located at levels L1–L3 than at T6–T8 or T9–T12 (p = 0.006).

CONCLUSION

Lung function impairment was seen in more severe spinal deformities, proximally-located curvature and older patients.     

Clinics in diagnostic imaging (152). Right lower lobe segmental pulmonary embolus.

A 56-year-old man presented to the Accident and Emergency Department with pleuritic chest pain of sudden onset. He gave a history of short-distance air travel ten days earlier. Chest radiograph showed a peripheral-based opacity in the right lower zone, which was not seen in a previous study done three months ago, suggestive of Hampton’s hump. The D-dimer level was raised. Computed tomography pulmonary angiography confirmed the diagnosis of pulmonary embolism in a right lower lobe segmental branch, with adjacent collapsed lung, consistent with lung infarction. The patient was started on heparin injection with significant relief of his symptoms. The clinical and imaging features of pulmonary embolism are described, with emphasis on the historical radiographic signs and the current dual-energy computed tomography innovations.     

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.     

Overlap syndrome between chronic obstructive pulmonary disease and obstructive sleep apnoea in a Southeast Asian teaching hospital

INTRODUCTION

Overlap syndrome between obstructive sleep apnoea (OSA) and chronic obstructive pulmonary disease (COPD) is important but under-recognised. We aimed to determine the prevalence of overlap syndrome and the predictors of OSA in patients with COPD.

METHODS

Patients aged ≥ 40 years were recruited from a dedicated COPD clinic and underwent overnight polysomnography. A diagnosis of OSA was made when apnoea-hypopnoea index (AHI) was ≥ 5.

RESULTS

In all, 22 patients (aged 71 ± 9 years), predominantly men, were recruited. Mean values recorded were predicted forced expiratory volume in the first second percentage 55 ± 15; body mass index 23.7 ± 6.5 kg/m²; Epworth Sleepiness Scale score 5.6 ± 5.8; and AHI 15.8 ± 18.6. Among the 14 patients with OSA (prevalence of overlap syndrome at 63.6%), the mean number of hospital visits for COPD exacerbations in the preceding one year was 0.5 ± 0.7. Patients with overlap syndrome had worse modified Medical Research Council dyspnoea scale scores and a lower percentage of rapid eye movement (REM) sleep than patients without. There were no other statistical differences in lung function or sleep study indices between the two patient groups.

CONCLUSION

The majority of our patients had overlap syndrome and minimal exacerbations, and were not obese or sleepy. Significant differences between patients with and without overlap syndrome were seen in two aspects – the former was more dyspnoeic and had less REM sleep. Our findings suggest that standard clinical predictors cannot be used for patients with overlap syndrome, and therefore, a high index of suspicion is needed.     

Large bowel obstruction complicating a posttraumatic diaphragmatic hernia

Posttraumatic diaphragmatic hernia is a rare cause of large bowel obstruction, and can present weeks or years after the initial trauma. Herein, we report the case of a 28-year-old man who presented with signs and symptoms of bowel obstruction nine months after he had a stab wound to his left chest. Chest radiography showed multiple air-fluid levels in the right upper quadrant, an air-fluid level in the left thoracic cavity and significant free air under the diaphragm. Exploratory laparotomy revealed a contaminated abdomen with perforations in the caecum and proximal transverse colon, and a 4 cm × 4 cm defect in the left posterolateral (septal) aspect of the diaphragm, which was closed with a nonabsorbable suture. Posttraumatic diaphragmatic hernias should be part of the differential diagnosis for patients with bowel obstruction, especially if there is a history of trauma. Radiography is useful in facilitating a quick diagnosis.     

Clinics in diagnostic imaging (162). Meckel’s diverticulum

A 28-year-old Chinese man presented with acute bleeding per rectum. Computed tomography showed a posterior outpouching arising from the distal ileum. The outpouching had hyperaemic walls, but no active contrast extravasation was detected. Technetium-99m pertechnetate scintigraphy showed focal areas of abnormal uptake in the right side of the pelvis, superior and posterior to the urinary bladder. These areas of uptake appeared simultaneously with the gastric uptake and demonstrated gradual increase in intensity on subsequent images. The diagnosis of Meckel’s diverticulum was confirmed on surgery and the lesion was resected. The clinical and imaging features of Meckel’s diverticulum are discussed.     

Paediatric rheumatology: a subspecialty in its infancy that is making leaps and bounds

Paediatric rheumatology is an exciting field exploding with new knowledge of autoimmune and autoinflammatory conditions and how to treat them. It is, however, a relatively new subspecialisation in Asia. There is thus a great need to educate the public and medical community about paediatric rheumatic diseases so that children with such conditions are given the highest possibility of achieving normal function in their daily lives.     

Polymorphism of ZBTB17 gene is associated with idiopathic dilated cardiomyopathy: a case control study in a Han Chinese population

Background

Dilated cardiomyopathy (DCM) has been extensively investigated for many years, but its pathogenesis remains uncertain. The ACTC1 gene was the first sarcomeric gene whose mutation was shown to cause DCM; recent studies have indicated that the HSPB7 and ZBTB17 genes are also associated with DCM. To assess the potential role of these three genes in DCM, we examined 11 single nucleotide polymorphisms (SNPs) in the ZBTB17, HSPB7 and ACTC1 genes: namely, rs10927875 in ZBTB17; rs1739843, rs7523558, and rs6660685 in HSPB7; rs533021, rs589759, rs1370154, rs2070664, rs3759834, rs525720 and rs670957 in ACTC1.

Methods

A total of 97 DCM patients and 189 controls were included in the study. All SNPs were genotyped by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS).

Results

The genotype of SNP rs10927875 in ZBTB17 (OR=5.19, 95% CI =1.00 to 27.03, P=0.05) was associated with DCM in a Han Chinese population. There was no difference in genotype or allele frequencies in ACTC1 or HSPB7 between DCM patients and control subjects.

Conclusion

The ZBTB17 polymorphism rs10927875 appears to play a role in the susceptibility of the Han Chinese population to DCM.