Comparison of Clinical Outcomes of Calcified and Non-Calcified Coronary Artery Lesion Intervention Under IVUS Guidance.

OBJECTIVE: To evaluate the clinical results of intravascular ultrasound (IVUS)-guided intervention for calcified coronary artery lesions. STUDY DESIGN: Observational study. Place and Duration of the Study: Department of Medicine, The Aga Khan University Hospital, Karachi, from January 2013 to January 2020. METHODOLOGY: A cohort of 134 consecutive patients who underwent intravascular ultrasonography-guided assessment of coronary arteries were included. Patients were divided into two groups: those with coronary artery calcification (CAC, n=77) and those without (non-CAC, n=57). The two groups were compared for their clinical characteristics, management, in-hospital events, follow-up, and major adverse cardiovascular events (MACEs). RESULTS: The mean follow-up duration was 40.3 ± 30.1 months. Most of the patients were male (n=97, 72.3%), and the mean age was 63.1 ± 12.9 years. In the CAC group, age was the most common risk factor, followed by dyslipidaemia (n=68, 88%), hypertension (n=64, 83%), and Diabetes mellitus (n=44, 57%). CAC group patients were more commonly presented with acute coronary syndrome (n=59, 76.6%), had prior PCI (n=40, 52%), had more LM disease (n=34, 44%, p=0.005), and a significant number of prior stent-ISR (n=27, 35%, p=0.024). Those who had CAC had higher MACE. CONCLUSION: Patients with CAC had more co-morbidities and commonly presented with acute coronary syndrome. MACEs frequency was recorded higher in the CAC group although the results were not statistically significant. KEY WORDS: Coronary artery calcification, Intravascular imaging, Coronary artery disease, Target vessel revascularisation, Percutaneous coronary intervention.

Prevalence of familial hypercholesterolemia in a country-wide laboratory network in Pakistan: 10-year data from 988, 306 patients.

INTRODUCTION: Familial hypercholesterolemia (FH) is a modifiable risk factor for premature coronary heart disease but is poorly diagnosed and treated. We leveraged a large laboratory network in Pakistan to study the prevalence, gender and geographic distribution of FH. METHODOLOGY: Data were curated from the Aga Khan University Hospital clinical laboratories, which comprises of 289 laboratories and collection points spread over 94 districts. Clinically ordered lipid profiles from 1st January 2009 to 30th June 2018 were included and data on 1,542,281 LDL-C values was extracted. We used the Make Early Diagnosis to Prevent Early Death (MEDPED) criteria to classify patients as FH and reported data on patients with low-density liporotein -cholesterol (LDL-C) ≥ 190 mg/dL. FH cases were also examined by their spatial distribution. RESULTS: After applying exclusions, the final sample included 988,306 unique individuals, of which 24,273 individuals (1:40) had LDL-C values of ≥190 mg/dL. Based on the MEDPED criteria, 2416 individuals (1:409) had FH. FH prevalence was highest in individuals 10-19 years (1:40) and decreased as the patient age increased. Among individuals ≥40 years, the prevalence of FH was higher for females compared with males (1:755 vs 1:1037, p < 0.001). Median LDL-C for the overall population was 112 mg/dL (IQR = 88-136 mg/dL). The highest prevalence after removing outliers was observed in Rajan Pur district (1.23% [0.70-2.10%]) in Punjab province, followed by Mardan (1.18% [0.80-1.70%]) in Khyber Pakhtunkhwa province, and Okara (0.99% [0.50-1.80%]) in Punjab province. CONCLUSION: There is high prevalence of actionable LDL-C values in lipid samples across a large network of laboratories in Pakistan. Variable FH prevalence across geographic locations in Pakistan may need to be explored at the population level for intervention and management of contributory factors. Efforts at early diagnosis and treatment of FH are urgently needed.

Leveraging Clinical Digitized Data to Understand Temporal Characteristics and Outcomes of Acute Myocardial Infarctions at a Tertiary Care Medical Centre in Pakistan from 1988-2018 - Methods and Results.

Background and Objective: Few data exist on trends in acute myocardial infarction (AMI) patterns spanning recent epidemiological shifts in low middle-income countries (LMICs). To understand temporal disease patterns of AMI characteristics and outcomes between 1988-2018, we used digitized legacy clinical data at a large tertiary care centre in Pakistan. Methods: We reviewed digital health information capture systems maintained across the Aga Khan University Hospital and obtained structured elements to create a master dataset. We included index admissions of patients >18 years that were discharged between January 1, 1988, and December 31, 2018, with a primary discharge diagnosis of AMI (using ICD-9 diagnoses). The outcome evaluated was in-hospital mortality.Clinical characteristics derived from the electronic database were validated against chart review in a random sample of cases (k 0.53-1.00). Results: The final population consisted of 14,601 patients of which 30.6% (n = 4,470) were female, 52.4% (n = 7,651) had ST elevation MI and 47.6% (n = 6,950) had non-ST elevation MI. The median (IQR) age at presentation was 61 (52-70) years. Overall unadjusted in-hospital mortality was 10.3%. Across the time period, increasing trends were noted for the following characteristics: age, proportion of women, prevalence of hypertension, diabetes, proportion with NSTEMI (all ptrend < 0.001). In-hospital mortality rates declined significantly between 1988-1997 and 2008-2018 (13.8% to 9.2%, p < 0.001). Conclusions: The patterns of AMI have changed over the last three decades with a concomitant decline in in-hospital mortality at a tertiary care centre in Pakistan. Clinical digitized data presents a unique opportunity for gaining insights into disease patterns in LMICs.

Etiology, clinical characteristics, and outcome of infective endocarditis: 10-year experience from a tertiary care center in Pakistan.

This study was conducted to assess the clinical characteristics, causative agents, complications, and outcomes of infective endocarditis (IE) among patients presenting to our tertiary care center over the last decade. This retrospective cohort study included all adult patients admitted to the Aga Khan University Hospital with the diagnosis of IE over a ten-year period from 2010 to 2020.  Outcomes variables included complications during hospitalization, surgical intervention, mortality, and length of stay. We identified a total of 305 cases out of which 176 (58%) were males and 129 (42%) were females. The mean age of the patients was 46.9±18.8 years. 95 (31%) had prosthetic valves in place. Staphylococcus aureus was isolated in 54 (39%) patients followed by coagulase-negative Staphylococcus in 23 (17%). Echocardiography revealed vegetations and abscesses in 236 (77%) and 4 (1%) patients, respectively. The most common valvular complication was mitral valve regurgitation found in 26 (9%) patients, followed by tricuspid valve regurgitation in 13 (4%) patients and aortic valve regurgitation in 11 (3%) patients. Furthermore, 81 (27%) patients suffered from heart failure and 66 (22%) from a stroke during hospitalization. The mean hospital length of stay was 10.4 ± 10.6 days. 64 (21%) patients required surgical repair and the overall mortality rate was 25%. Prosthetic valve endocarditis (OR = 3.74, 95% CI = 2.15-6.50, p<0.001), chronic kidney disease (OR = 2.51, 95% CI = 1.15-5.47, p=0.036), previous stroke (OR = 2.42, 95% CI = 1.18-4.96, p=0.026), and ischemic heart disease (OR = 3.04, 95% CI = 1.50-6.16, p=0.003) were significantly associated with an increased risk of mortality. In conclusion, our study provided valuable data on the clinical characteristics and outcomes of patients with IE in a developing country. S. aureus was the most common causative agent. Heart failure and stroke were the most common complications. The presence of prosthetic valves, history of chronic kidney disease, ischemic heart disease and previous stroke were associated with a significantly increased risk of mortality. Surgical management was not associated with improved outcomes.

Acute Myocardial Infarction After Coronavirus Vaccine: A Rare Adverse Effect.

A 61-year-old male presented to the emergency department with left arm and jaw pain for three hours which started 90 minutes after receiving the first dose of Moderna vaccine for coronavirus disease 2019 (COVID-19). He had a prior history of ischemic heart disease. Initial investigations confirmed the diagnosis of acute coronary syndrome. The patient was managed for non-ST-elevation myocardial infarction and percutaneous coronary intervention to the right posterior descending artery was done, and he was discharged after two days of hospital stay. As the patient was doing well for many years and was compliant with medications, this event was likely triggered by the coronavirus vaccine. Healthcare providers should be aware of the side effects of the vaccine and further investigations should be carried out in high-risk patients before vaccination. However, worldwide coronavirus vaccination programs play a significant role to halt this pandemic and these rare adverse side effects of the vaccine should never discourage people from the vaccination but monitoring of evolving data by the concerned authorities is very important so that these events can be prevented in future.

Clinical characteristics and prognostic factors of atrial fibrillation at a tertiary center of Pakistan - From a South-Asian perspective - A cross-sectional study.

BACKGROUND: There is lack of large data from South-Asian region on atrial fibrillation and it is imperative that clinical presentation, prognostic factors, management pursued, and outcomes are known for this part of the world. Once collective evidence for the region is known, region-specific guidelines can be laid forward. OBJECTIVES: To evaluate clinical characteristics and prognostic factors of atrial fibrillation at a tertiary care center of Pakistan. METHODS: This was a retrospective study conducted at a tertiary care center of Pakistan. Period of study ranged from July-December 2018. All hospitalized patients who were admitted with atrial fibrillation as a primary or associated diagnosis were enrolled. RESULTS: A total of 636 patients were enrolled. The mean age was 68.5 ± 12 years and 49.5% (315) were male. 90.6% of the patients were admitted via emergency room. Majority (59.9%) had previously known AF and 40% developed new-onset AF during the hospital stay. Hypertension was the most common co-morbid condition (85.4%) followed by Diabetes Mellitus (40.1%). At least 9% had rheumatic heart disease. The median CHA2DS2VASc and HASBLED scores were 4 and 2 respectively. More than one-third of patients had sepsis as a primary diagnosis (36.8%). The in-hospital mortality of patients with atrial fibrillation was 6.7%. Patients with new-onset AF had higher mortality. Sepsis and stroke were independently associated with a higher mortality. There was no significant difference in median CHA2DS2VASc and HASBLED scores for patients with new-onset and previously known AF. On discharge, 83% of the eligible patients received oral anticoagulation. CONCLUSION: There was higher prevalence of chronic co-morbid conditions in the studied population leading to a higher CHA2DS2VASC Score. Sepsis and stroke were independently associated with higher in-hospital mortality.

Distal transradial artery access for coronary angiography in a patient having rheumatoid arthritis-related severe arthropathies.

Conventional radial access has become the default access for coronary angiography. Sometime, it is difficult to take a conventional radial access, especially in patients having severe arthropathies leading to limited wrist joint mobility. In such scenarios, distal transradial access (dTRA) can be adopted. We describe a case of an elderly male patient having rheumatoid arthritis with arthropathies. He presented to us with unstable angina; coronary angiogram was advised for ischaemia assessment. Right dTRA was adopted due to severe joint deformity at wrist joint, limiting joint extension. A successful coronary angiogram was performed via the right dTRA without major discomfort and complications. Haemostasis was secured with TR band radial artery compression device. In this case report, we have evaluated the importance of practising dTRA in a patient with severe arthropathies.

Clinical Outcomes of Physiologically-guided Revascularisation.

OBJECTIVE: To assess the clinical outcomes of revascularisation based on fractional flow reserve (FFR) and/or instantaneous wave-free ratio (iFR). STUDY DESIGN: Descriptive study. PLACE AND DURATION OF STUDY:  Department of Medicine, The Aga Khan University Hospital, Karachi from January 2012 to January 2020. METHODOLOGY:  A cohort of patients having moderate to severe coronary stenosis, undergoing coronary revascularisation based on invasive physiological assessment (FFR or iFR) were assessed. The participants were divided into the revascularisation-deferred group and the revascularization-performed group, based on the physiological results. Cox-proportional hazard model building was done, using a stepwise approach by assessing all plausible interactions and considering p-value ≤0.05 as statistically significant. RESULTS:  The frequency of major adverse cardiac event (MACE) and target vessel revascularisation was 8.4% and 3.2% in the revascularisation-performed group as compared to 6.4% and 3.2% in the revascularisation-deferred group. In adjusted models, no statistically significant difference was noted in MACE when comparing the revascularisation-performed group with a deferred group. CONCLUSION:  Revascularisation guided by invasive physiological assessment with FFR or iFR is clinically safe and led to better resource utilisation. Key Words: Fractional flow reserve, Instantaneous wave-free ratio, Invasive physiological assessment, Low-middle income country.

Clinical Outcomes and Prevalence of Intravascular Ultrasound Use at a Tertiary Care Hospital in a South Asian Country.

OBJECTIVES: Intravascular ultrasound (IVUS) plays a pivotal role in the current era of coronary interventions. We aimed to determine the prevalence of IVUS use and clinical outcomes of IVUS-guided percutaneous treatment of coronary arteries lesions in a South Asian country. MATERIAL AND METHODS: It is a retrospective observational study, a total of 134 consecutive patients having done IVUS, was enrolled from January 2013 to March 2020 at a single center. RESULTS: Out of 134 patients, 97 (72.4%) were male with a mean age of 63.1 ± 12.9 years. The prevalence of IVUS in our center was 3.0%. The most frequent comorbidity observed was dyslipidemia, n = 111 (82.8%). Non-ST-elevation myocardial infarction, n = 50 (37.3%), was the common mode of presentation. On coronary angiogram, the left main (LM) disease was found in n = 46 (34.3%), however, single-vessel disease, n = 51 (38.1%), was most commonly noted. IVUS utilization was higher in the left anterior descending, n = 94 (70.1%), followed by LM, n = 46 (34.3%). The LM mean minimal luminal area was 6.0 ± 2.6 mm2 and minimal luminal diameter was 4.53 mm ± 0.6 (mean). The coronary artery dissection was noted in n = 15 (11.2%). The mean duration of follow-up in our study was 40.3 ± 30.1 months. Major adverse cardiac events (MACEs) were recorded in n = 13 (9.7%), which included heart failure, n = 4 (3%). Cardiovascular death and target vessel revascularization occurred in n = 3 (2.2%). CONCLUSION: IVUS results in a significant decrease in MACE. Our data might support the broader use of IVUS in both developed and in our part of the world.