Positional syncope occurring just at the right time in a patient with a permanent pacemaker: A case report.

We present an unusual case of positional syncope occurring years after pacemaker implantation. Syncope was caused by a pacemaker lead fracture, which resulted from subclavian crush syndrome. The syncope occurred incidentally during hospital admission and was timely diagnosed using an integrated approach of history taking, examination findings, device interrogation and radiographic parameters. The patient subsequently underwent lead and device alteration which led to resolution of her symptoms.

Successful radio-frequency catheter ablation of two cases of supraventricular tachycardia via a left-sided inferior vena cava.

Congenital venous anomalies are uncommon, incidental findings encountered during adult interventional electrophysiology procedures. Femoral venous access is conventionally used during cardiac electrophysiology studies to gain access to the heart. The chance finding of an inferior vena cava anomaly may preclude the performance of these procedures from the femoral approach. We describe two cases in which we were able to successfully perform different radiofrequency catheter ablation procedures in the presence of an unusual venous anomaly, the left-sided IVC.

Cardiac electrophysiologic procedures - A ten years' experience at National Institute of Cardiovascular Diseases, Karachi.

OBJECTIVE: To review 10 years of clinical practice of cardiac electrophysiology study and radiofrequency catheter ablation in the treatment of supraventricular tachycardia. METHODS: The retrospective chart review was conducted at the National Institute of Cardiovascular Diseases, Karachi, and comprised records of all patients who underwent electrophysiological study and / or radiofrequency catheter ablation from January2007 to December 2016. SPSS 21 was used for data analysis. RESULTS: Of the 627 patients, 335(53.4%) were females. The overall mean age was 40.99}13.59 years. The major indication for procedure was supraventricular tachycardia 376(59.97%). Final electrophysiological study diagnosis was typical slow fast atrioventricular nodal re-entrant tachycardia in 303(48.3%) patients. The overall success rate was 472(75.3%). Procedure-related complications were reported in 25(4%) patients, and there was 1(0.15%) mortality. CONCLUSIONS: Cardiac electrophysiology studies and radiofrequency catheter ablation were found to be an effective and safe method for diagnosis and treatment of supraventricular tachycardia.

Un-ruptured Non-Coronary Sinus of Valsalva Aneurysm with Complete Heart Block.

Sinus of Valsalva aneurysm is a rare cardiac anomaly with wide spectrum of clinical presentation ranging from asymptomatic state to dreadful complications due to compression of vital surrounding structures or aortic dissection. There are only few reported cases of sinus of Valsalva aneurysm presented with cardiac arrhythmias including complete heart block. We herein, present a case of a 50 year male who presented with complete heart block. A large noncoronary sinus of Valsalva aneurysm compressing the surrounding atrioventricular junctional tissue was detected incidentally during echocardiographic study, which was considered to be the cause of patient's complete heart block. This case report implies the importance of clinical suspicion of secondary causes like sinus of Valsalva aneurysm in patients with complete heart block and utility of echocardiography in the evaluation of heart block patients.

Factors affecting outpatient cardiac rehabilitation attendance after acute myocardial infarction and coronary revascularization--a local experience.

OBJECTIVE: To determine factors affecting cardiac rehabilitation attendance after myocardial infarction and coronary revascularization. METHODS: A cross-sectional study was conducted on 416 patients admitted in Tabba Heart Institute, Karachi from December 2010 to May 2011. Patients admitted with diagnosis of acute myocardial infarction (AMI) or who underwent elective coronary artery bypass graft surgery (CABG) or percutaneous coronary intervention (PCI) procedures were offered cardiac rehabilitation (CR). Out of these, patients who enrolled in 6 weeks outpatient CR programme were followed for number of CR sessions and their socio-demographic and clinical data were collected. Data was analyzed by Statistical Package for Social Sciences (SPSS) software, version 15.0. Chi-square test was applied to test association between categorical variables and Student's t-test for continuous variables. RESULTS: Out of 416 patients identified, only 151 patients (36.2%) enrolled and attended the CR programme. Of the 151 attendees, 111 (73.4%) patients subsequently completed more than 6 weeks of outpatient CR programme. We found significant association between CR attendance and easy access to the programme, elective CABG procedure, employment status, presence of diabetes or hypertension and baseline level of exercise (all p < or = 0.01). No association was found between CR attendance and patient age, gender, body mass index or different economic groups. CONCLUSION: Attendance rates of patients attending outpatient CR programme after AMI or coronary revascularization procedures are suboptimal. Patients who underwent elective CABG surgery and had easy access to the CR programme had better attendance. Factors contributing to poor attendance rates at CR programmes in developing countries need to be explored and subsequently addressed.

Beyond The Pleasure Principle - Fatal Cardiac Arrhythmias After Ingestion Of An Herbal Medication.

There is increasing popularity in the use of herbal medicine for different ailments as these natural products are considered safer than conventional medicines; however, their use in dosage exceeding prescribed limits can result in serious toxic side effects. We present a case of a 63-year old male who presented with complaints of restlessness, nausea, vomiting and tingling sensation on his body and ECG evidence of bi-directional ventricular tachycardia. On interrogation, it was revealed that the patient had self-prepared and consumed large quantity of an herbal medication (containing toxic aconite roots) as therapy for erectile dysfunction resulting in a fatal outcome.

Routine Measurement of Thyroid Stimulating Hormone in Patients Presenting With Third-Degree Atrioventricular Block: Do We Really Need It?

Background Hypothyroidism can be a cause of sinus bradycardia. However, thyroid laboratory evaluation is often performed routinely in patients with complete heart block (CHB) though there is little data to support this practice. This study aimed to assess the frequency of thyroid dysfunction in patients presenting with CHB without clinical features of hypothyroidism. Methodology All patients referred for permanent pacemaker implantation for CHB were included in this cross-sectional study. Patients with known thyroid disorder or clinical features of thyroid disorder were excluded. Demographic, electrocardiography (EKG), and routine thyroid stimulating hormone (TSH) screening results were recorded. Results A total of 102 patients with complete atrioventricular (AV) block were enrolled in the study of which 50.0% (51) were male. The mean age was 61.09 ± 11.74. Co-morbidities included diabetes mellitus 44.1% (45), smoking 36.3% (37), and hypertension 55.9% (57). Mean EKG atrial rate was 82.97 ± 31.31 mmHg with a mean ventricular escape rate of 36.17 ± 5.93. Permanent pacemakers were implanted in all of the patients. Only one patient had an abnormal TSH. Conclusions We found a very low prevalence of thyroid dysfunction among patients without clinical features of thyroid dysfunction presenting with third-degree AV block. This calls for cautious prescription of thyroid testing in clinically euthyroid patients.

To determine the safety and success of transradial coronary angiography and angioplasty--a local experience.

OBJECTIVE: To determine the safety and success of transradial coronary angiography and angioplasty in a Pakistani population. METHODS: This was a prospective study on 264 consecutive patients undergoing transradial coronary angiography (TRCAG) and angioplasty (TRCAP) at Tabba Heart Institute, Karachi between November to December 2008. All patients enrolled in the study underwent Allen's test to ensure dual arterial supply to the hand. Modified Allen's test was performed only when Allen's test was abnormal. Patients were excluded from the study if they had abnormal Allen's and modified Allen's test, were on haemodialysis or had abnormal serum creatinine level. The main outcome measures were success rate and complications of TRAG and TRCAP. RESULTS: The mean age was 57 +/- 11.08 years with 199 (75.4%) males and 64 (24.6%) females. A total of 182 (76.3%) coronary angiographies and 82 (76.8%) coronary angioplasties were preformed from the trans-radial route in the study period. Overall procedural success rate was 94% for TRCAG with mean procedure time of 23.74 +/- 6.26 minutes and mean fluoroscopy time of 5.65 +/- 2.3 minutes. The success rate for TRCAP was 93.6% with mean procedure time of 62 +/-10.6 minutes and mean fluoroscopy time of 15.78 +/- 8.90 minutes. Only 1 patient had mild forearm haematoma and asymptomatic radial artery occlusion occurred in 4 (1.5%) study patients. CONCLUSION: Trans-radial artery cannulation is a safe and successful route for performance of coronary procedures. It can be used as an acceptable alternate to transfemoral approach.

Correlation of cardiac troponin I levels (10 folds upper limit of normal) and extent of coronary artery disease in non-ST elevation myocardial infarction.

OBJECTIVE: To determine the correlation of cardiac troponin I (cTnI) 10 folds upper limit of normal (ULN) and extent of coronary artery disease (CAD) in Non-ST-elevation myocardial infarction (NSTEMI). METHODS: A cross-sectional study was conducted on 230 consecutive NSTEMI patients admitted in Tabba Heart Institute, Karachi between April to December 2008. cTnI was measured using MEIA method. All patients underwent coronary angiography in the index hospitalization. Stenosis > or = 70% in any of the three major epicardial vessels was considered significant CAD. Extent of CAD was defined as significant single, two or three vessel CAD. Chi-square test was applied to test the association between cTnI levels and CAD extent. RESULTS: Out of 230 patients, in 111 patients with cTnI levels < or = 10 folds upper limit of normal (ULN), 25 (22.52%) had single vessel, 40 (36%) had two vessel and 34 (30.6%) had three vessel significant CAD, whereas in 119 patients with cTnI levels > 10 folds ULN, 23 (19.3%) had single vessel, 37 (31.1%) had two vessel and 55 (46.2%) had three vessel significant CAD. The results suggest that there was an insignificant association between the cTnI levels and single vessel, two vessel and the overall CAD extent (p = 0.35, p = 0.21 and p= 0.13 respectively), however there was a statistically significant association between the cTnI levels and three vessel CAD (p < 0.04). CONCLUSION: Higher cTnI levels are associated with an increased proportion of severe three vessel CAD involvement. Prompt identification and referral of this patient subset to early revascularization strategies would improve clinical outcomes.

Correlation of thrombolysis in myocardial infarction (TIMI) risk score with extent of coronary artery disease in patients with acute coronary syndrome.

OBJECTIVE: To determine the correlation of thrombolysis in myocardial infarction (TIMI) risk score with extent of coronary artery disease (CAD) in patients with acute coronary syndrome (ACS). METHODS: We conducted a descriptive study among 200 consecutive patients admitted with ACS at Tabba Heart Institute, Karachi from June to December 2008. The TIMI risk score was stratified on seven standard variables. The extent of CAD was evaluated on angiography and significant CAD was defined as > or =70% stenosis in any one of the three major epicardial vessels. RESULTS: The mean age of the sample was 58.53 +/- 10.64 years. Out of 200 patients, there were 142 (71%) patients with TIMI score < or =4 (low and intermediate TIMI risk score) and 58 (29%) patients with TIMI score >4 (high TIMI risk score). Patients with TIMI score >4 were more likely to have significant three vessel CAD (62%) versus those with TIMI risk score <4 (46.2%), (p < 0.04). CONCLUSION: Patients with high TIMI risk score were more likely to have severe multivessel CAD compared with those with low or intermediate TIMI risk score. Hence, patients with TIMI score >4 should be referred for early invasive coronary evaluation to derive clinical benefit.

Localization Of Accessory Pathways In Wolff Parkinson White Syndrome Using R/S Ratios On Surface Ecgs.

BACKGROUND: This study was conducted to establish the accuracy of R/S ratios in localizing accessory pathways in Wolff Parkinson White Syndrome on surface ECGs. METHODS: This was a retrospective cross-sectional study from January 2002 till December 2016 conducted at National Institute of Cardiovascular diseases in Karachi, Pakistan. The sample included 157 patients with manifesting Wolff Parkinson White (WPW) Syndrome on a 12-lead surface ECG. As per the inclusion criteria, patients who had persistent or intermittent pre-excitation on surface ECG and had undergone electrophysiological study (EP) were included in the sample. Individuals with both successful and unsuccessful ablation procedures were included. RESULTS: The sample consisted of 62.4% males (n=98) and 37.6% females (n=59) with mean age being 35.36±12.44. Accessory pathways (APs) were identified on the left side in majority of the patients with 54.1% (n=85) while right sided pathways were seen in 42.1% (n=66). Moreover, the most common accessory pathway amongst the males was Left Anterior (LA) and Left Lateral (LL) with a percentage of 48%, followed by Right Posteroseptal (RPS) at 20.4%. As opposed to this, the most common pathways amongst the females turned out to be RPS at 33.9% followed by LL and LA at 32.2%. Furthermore, the test using ratios were most effective in identifying left sided APs with sensitivity 74.1% and was least sensitive in identifying right sided pathways (sensitivity=40.7%). However, it was highly specific in locating right sided pathways with specificity of 94.6% as opposed to 83.3% in the left side. Furthermore, mid-septum regions had a sensitivity and specificity of 66.7% and 69.6% respectively. CONCLUSIONS: This establishes the effectiveness of R/S ratios in determining the location of accessory pathway based on the surface ECG prior to the ablation procedure. Since the younger population is affected more commonly, prolonged exposure to ionizing radiation can cause long term complications therefore, by this means, the duration of exposure can be reduced.

Measurement of interatrial septal thickness by echocardiography in patients with moderate to severe rheumatic mitral stenosis undergoing percutaneous balloon mitral valvuloplasty.

BACKGROUND: Longstanding severe rheumatic mitral stenosis (MS) is associated with changes in the atrial chamber dimensions. It is not known whether there is an increased thickness of the inter-atrial septum (IAS) in patients with severe rheumatic mitral stenosis. The objective of this study was to evaluate pre-procedural IAS thickness by echocardiography in patients with moderate to severe rheumatic mitral stenosis undergoing percutaneous balloon mitral valvuloplasty (PBMV). METHODS: The thickness of the IAS was measured by transesophageal echocardiography (TEE) in 86 patients between 14 and 65 years of age. Patients with moderate to severe rheumatic mitral stenosis undergoing percutaneous mitral balloon valvuloplasty (PMBV) at the National Institute of Cardiovascular Diseases (NICVD), Karachi were recruited for this study. IAS thickness was measured by TEE using standard views and 3 different phases of cardiac cycles were evaluated. RESULTS: Out of 86 patients, almost three fourths (73.3%) were between 14 and 29 years of age and two thirds (62.8%) were females. Mean IAS thickness was 2.56 (SD 0.92) mm at anterior region (AR), 1.89 (SD 0.75) mm at fossa ovalis (FO), and 2.95 (SD 0.97) mm at posterior region (PR). None of the demographic and clinical groups showed any statistically significant difference in IAS thickness. CONCLUSIONS: Inter-atrial septum (IAS) thickness measurement does not change in the presence of moderate to severe rheumatic mitral stenosis as compared to the reported normal values of IAS thickness in cadaveric hearts.

Medication Adherence In Post Myocardial Infarction Patients.

BACKGROUND: Medication non-adherence after acute myocardial infarction is a global problem causing increased morbidity and mortality. This multifaceted problem has not been well studied in our part of the world. Our study aimed to determine the burden of medication non-adherence in post myocardial infarction patients. METHODS: This cross-sectional study was conducted at National Institute of Cardiovascular disease, Karachi, from December 2016 to June 2017. A total of 350 patients were included at the time of discharge after their first myocardial infarction (MI) of which follow up was completed for 315 patients. Baseline characteristics and discharged drug data were collected for each individual. Patients were called at 7th day, 1 and 3months post discharge and were assessed for the medication adherence using Morisky medication adherence scale. They were stratified accordingly into self-reported high, moderate and low groups. Chi- square test was used to determine significant relationship between variables. The level of significance was set at level of p-value ≤0.05. RESULTS: Among 315 patients, only 45% patients were adherent to prescribed drugs at 7th day follow up and the adherence further reduces to 19% at 3rd post MI month (p-value <0.001). High income, male gender, and presence of partner persistently showed significantly higher medication adherence. Factors like younger age, addiction and advance education showed higher adherence only in early follow up periods. However, presence of comorbidities, intervention and specific diagnosis had no significant impact. The most common stated reasons for non-adherence were forgetfulness and poor understanding of drugs. CONCLUSIONS: Adherence to prescribed medication in post myocardial infarction patients was found to be strikingly suboptimal, contributed by multiple factors. Modification of these factors would likely improve patient adherence to medication and eventually long-term outcome.

Extra pontine myelinolysis associated with hypophosphatemia.

We report a unique association of extra-pontine myelinolysis with severe hypophosphatemia developing in a young lady with a prolonged febrile illness and inadequate oral intake. The late identification of severe hypophosphatemia resulted in extra-pontine myelinolysis. Gradual improvement in clinical status was noticed with phosphate replacement and good supportive care.

Severe rhabdomyolysis due to drug overdose.

A case of a young girl is described who presented in a state of intoxication and later developed acute renal failure secondary to severe rhabdomyolysis. With vigorous fluid therapy she regained normal renal function. Biochemical testing finally confirmed over the counter drug overdose as the cause for this presentation.