Coronary Artery Bypass Grafting Following COVID-19 Infection: Difficulties and Challenges.

The COVID-19 pandemic has raised challenges and dilemmas to perform cardiac surgery in the patients following COVID-19 infection due to lasting adverse impacts of the disease on the lungs. A 74-years-old patient, recently infected by COVID-19, with previous myocardial infarction and multiple percutaneous coronary interventions, in-stent thrombosis to the left anterior descending artery, and low resting saturation, presented with chest pain and underwent urgent coronary artery bypass grafting. His postoperative period remained challenging due to high oxygen requirements. He had otherwise an uneventful recovery and was discharged on domiciliary oxygen, which was weaned off over three months and he continues to do well at six months of follow-up. Keywords: Cardiac surgery; COVID-19; coronary artery bypass surgery; pandemic.

Double Aortic Arch with Coarctation of Aorta in an Adolescent: Unraveling the Vascular Ring.

We report the case of a 12-year-old girl with balanced double aortic arch with coarctation of the aorta presenting with symptoms of respiratory and swallowing difficulty. On investigation, the patient had a double aortic arch with coarctation and clinically nonsignificant disease in the infrarenal aorta. Division of the nondominant aortic arch was done through a left thoracotomy, along with resection of the coarctation segment and placement of an interposition Dacron tube graft.

Door-to-balloon time and the determining factors in a tertiary cardiac center in Nepal.

BACKGROUND: Door-to-balloon (DTB) time of 90 min during primary angioplasty is considered as the benchmark duration. Shorter DTB time is preferable, and longer duration can have poor clinical outcomes. METHODS: A cross-sectional observational study of three months in Shahid Gangalal National Heart Center was conducted in which all patients undergoing primary angioplasty were included. The DTB time was calculated, and the different determining factors were studied. RESULTS: Seventy-nine patients undergoing primary percutaneous intervention were studied. The median DTB time was 79 minutes (Interquartile range [IQR] 59-115 min). Forty-six (58.2%) patients had a DTB time of less than 90 min. DTB time varied significantly with direct visit vs transfer (p = 0.029) and office time visit (9 am-5 pm) vs off time (5 pm-9 am) (p = 0.012). DTB time did not differ between any infarct-related vessels (p = 0.471), number of vessels involved (p = 0.638), and the added procedures (defibrillation, thrombosuction, and temporary pacemaker insertion) (p = 0.682) during angioplasty. No significant differences were recorded according to age (p = 0.330), gender (p = 0.254), hypertension (p = 0.073), diabetes (p = 0.487), heart failure (p = 0.316), and baseline left ventricular ejection fraction (LVEF) (p = 0.819). CONCLUSION: The median DTB time in primary angioplasty was less than 90 minutes. The significant determining factors were timing of hospital visit (office vs off time) and type of visit (direct vs transfer). There can be improvement in factors determining DTB time to lower it further.

Prehospital Events in ST- Elevation Myocardial Infarction Undergoing Primary Angioplasty.

INTRODUCTION: Pre-hospital delay includes time from onset of symptoms of myocardial infarction till arrival to emergency room of the hospital. This defines time from symptom onset to first medical contact and first medical contact to emergency room. This study aims to study the prehospital events and determining factors in patients undergoing primary angioplasty. METHODS: This was a cross sectional study in Shahid Gangalal National Heart Centre for three months. Timings of chest pain, first medical contact time, transfer time to hospital and overall pre-hospital time for PCI and risk factors were analysed. RESULTS: There were 79 cases with 66 (83.5%) males and 13 (16.5%) females with mean age 56±11.2 years. Risk factors were 60 (75.9%), smoking, 47 (59.5%) hypertension, 25 (31.6%) diabetes, 22 (27.8%) dyslipidaemia and 16 (20.3%) heart failure. Chest pain was maximum in 5 to 9 AM. The median prehospital delay was 300 minutes (5.0 hours) of which symptom to first medical contact was 165 minutes and first medical contact to hospital was 80 minutes. The longer median prehospital delay for hypertension, diabetes, female and age ≥50 years and the shorter for male, age less than 50 years, dyslipidemia and heart failure, though not statistically significant. Private transport was the preferred from symptom to first medical contact and ambulance for first medical contact to emergency room. Patients received in ER had aspirin 72 (91.1%), atorvastatin 54 (68.4%) and double anti-platelets 45 (57%). CONCLUSIONS: Chest pain was common in morning and the prehospital delay can be minimized by improving time from symptom to first medical contact and first medical contact to Emergency room.

Percutaneous transvenous mitral commissurotomy in mitral stenosis and left atrial appendage clot patients in special conditions: Hospital-based study.

BACKGROUND: The percutaneous transvenous mitral commissurotomy is an important procedure for the treatment of mitral stenosis. A lot of mitral stenosis cases have left atrial appendage clot which precludes the patient from the benefit of this procedure. The aim of the study was to study the feasibility and safety of the procedure in a patient with appendage clot in the setup of certain urgent conditions. METHOD: All cases of mitral stenosis with significant dyspnea and mitral valve area <1.5cm2 with left atrial appendage clot and a condition which would preclude the patient from continuing on anticoagulation and needed urgent intervention were included in the study. From January 2011 to December 2013, twenty patients coming to Shahid Gangalal National Heart Centre, Kathmandu were selected for the procedure with conventional sampling technique. Informed written consent was obtained from the patients explaining all possible complications. The approval of the study was taken from the ethical committee of the hospital. RESULT: Mean mitral valve area increased from 0.90cm2 (SD±0.14) to 1.5cm2 (SD±0.21) (p=0.02). Left atrial mean pressure decreased from mean of 20 to 10mmHg. Subjective improvement was reported in all. All of the patients had fulfilled criteria for successful PTMC. There was no mortality during hospital stay or in one-week follow-up period. There were no neurological complications or any need for emergency surgery. CONCLUSION: The immediate result of percutaneous transvenous mitral commissurotomy in selected cases of mitral stenosis with left atrial appendage clot is safe and acceptable in certain urgent situations in experienced hands.

Carotid intima-media thickness (CIMT) and carotid plaques in young Nepalese patients with angiographically documented coronary artery disease.

BACKGROUND: Carotid intima-media thickness (CIMT) and carotid plaques are non-invasive surrogate markers of early evaluation of coronary artery disease (CAD) and sub clinical atherosclerosis. The objective of the study was to evaluate CIMT and carotid plaques in less than 45 years old Nepalese patients with angiographically proven CAD. METHODS: A total of 54 patients with angiographically documented CAD at less than 45 years of age were enrolled. CAD was confirmed by coronary angiography. Demographic profile was obtained. High resolution B-mode ultrasound was used to detect the CIMT and carotid plaques. RESULTS: The study population included 44 males and 10 females, with a mean ± SD age of 38.4±4.3 years (range, 25-44 years). Cardiovascular risks factors included smoking in 81%, Hypertension in 52%, diabetes in 19% and alcohol consumption in 78% of patients. Lipid profile (mean ± SD) was normal except for elevated triglyceride (TG) levels of 204±130.8 mg/dL. By angiography, 64.8% had single vessel disease, 26% had double vessel disease and 9.2% had triple vessel disease. Ultrasound detected either thickened CIMT or presence of plaques in 46 (85.2%) cases (group-A) and 8 (14.8%) had negative (normal) carotid study (group-B). Among the 46 patients with positive findings 63% had carotid plaques and 37% had thickened CIMT only. The majority (69%) of the carotid plaques were detected at the carotid bulbs. In total population, carotid plaque was detected in 53.7% of cases. There was no statistical significant difference of age, body mass index (BMI) and lipid level between group-A and group-B. CONCLUSIONS: Increased CIMT and carotid plaques are detected in majority of the young Nepalese patients with angiographically documented CAD. The majority of carotid plaques are detected at the carotid bulbs. Routine carotid ultrasound study in young individuals with CAD risk factors appears worthwhile.

Everolimus-eluting bioresorbable vascular scaffold (BVS) implantation in patients with ST-segment elevation myocardial infarction (STEMI).

AIMS: Recent studies have demonstrated favourable clinical outcomes for the everolimus-eluting bioresorbable vascular scaffold (BVS) ABSORB™ in patients with stable coronary artery disease. There are currently no data on its use in patients with ST-segment elevation myocardial infarction (STEMI). We assessed the safety and impact of BVS in the setting of primary percutaneous coronary intervention (PCI) in patients presenting with STEMI to our institution. METHODS AND RESULTS: A total of 11 patients who underwent primary PCI with intent for BVS implantation between October 2012 and April 2013 at our institution were included. Median follow-up period was 53.0 ± 45.9 days. One patient presented to the hospital with cardiogenic shock and subsequently died. The other 10 patients did not have any major adverse cardiac events (MACE). There were no acute or subacute stent thromboses at short-term follow-up. CONCLUSIONS: These are the first real-world data using BVS in patients with STEMI. The ABSORB™ BVS may be safely used in patients with STEMI undergoing primary PCI with favourable short-term outcome.

Role of dendritic cells in atherosclerosis.

Atherosclerosis is a lipid-related chronic inflammatory disease in which immune mechanisms play a pivotal role. The lesions are filled with large numbers of immune cells. During the last decade, dendritic cells have been identified in atherosclerotic plaques and are thought to play an important role in atherogenesis. Dendritic cells express major histocompatibility complex I and II, human leukocyte antigen-DR, CD1a, intercellular adhesion molecule-1, vascular cell adhesion molecule-1, and co-stimulatory molecule on their surfaces and this explains their unique ability to activate naive T cells. Factors such as oxidized low-density lipoprotein, hypoxia, nicotine, heat shock proteins, and altered nitric oxide synthase activity of the endothelium, all of which cause endothelial dysfunction, have a significant impact on dendritic cell adherence to endothelium and maturation. Mature dendritic cells are capable of presenting antigens to T cells, and activation of T cells leads to release of cytokines, which play an important role in the progression of disease. Drugs such as statins and diltiazem have been shown to protect endothelial function by inhibition of dendritic cell-endothelial cell interaction, and can be applied to delay the progression of cardiovascular diseases.

Percutaneous transvenous mitral commissurotomy.

Two hundred patients underwent Percutaneous transvenous mitral commissurotomy (PTMC) from January 2003 to July 2004. Seventy four percent of the patients were female. Age ranged from 10 years old to 61 years and mean age was 29 years. Twenty three percent of the patients were under 21 years of age. Atrial fibrillation was present in 32.0% of the cases. Mean mitral valve area increased from 0.90cm2 (+/- 0.14) to 1.82cm2 (+/- 0.21) (p = 0.018). Left atrial mean pressure decreased from 21 mmHg mean to 7 mmHg. Subjective improvement was reported in 98.0% of the patients immediately after the procedure. There was no mortality during the hospital stay or within the first month of the procedure. Significant mitral regurgitation of grade 3 was noted in 5 patients. Two developed severe mitral regurgitation. The complications were negligible. One had systemic embolisation during the procedure which recovered over a period of time. One developed deep vein thrombosis which recovered after treatment.

Taurine may prevent diabetic rats from developing cardiomyopathy also by downregulating angiotensin II type2 receptor expression.

OBJECTIVE: In diabetes, intracellular accumulation of sorbitol resulting from the high extracellular levels of glucose leads to depletion of intracellular compounds including taurine. This is associated with the development of late diabetic complications such as cardiomyopathy. The development of myocyte hypertrophy has been largely attributed to angiotensin II, whose growth properties are antagonized by taurine. However, the interaction between taurine, angiotensin II type2 receptor (AT2) and cardiomyopathy related to angiotensin II is still unknown. This study investigates the roles of taurine and AT2 in rats with streptozotocin (STZ)-induced diabetic cardiomyopathy. METHODS: Of 60 female 4-week-old Wistar rats, 8 were treated with common diet and the other 52 with high sugar/fat diet (during the whole experiment) to induce insulin resistance. At the 4th week, of the 52 rats, 7 treated with sodium citrate buffer (pH = 4.5) were grouped into control group1 (con1) and the other 45 were treated by intraperitoneal injection (I.P) with STZ to develop type 2 diabetes. At the 28th week, the maximal velocity decrease of pressure per second in left ventricle within the period of isovolumic relaxation (-dp/dt(max)) was detected by a cannula through right carotid artery. After the cannula operation, of the 45 rats, all the living 24 with -dp/dt(max)< or = 5250 mmHg/s, who had developed diabetic cardiomyopathy, were grouped as follows: 7 treated with double distilled H2O (I.P) were grouped into control group2 (con2). 8 treated with AT2 agonist (CGP42112A) (I.P) were grouped into experimental group1 (exp1). Another 9 treated with taurine (I.P) were grouped into experimental group2 (exp2). All injections lasted 4 weeks (Q.D) and the heart weight (HW) was recorded. To examine cardiomyocyte apoptosis index (CAI), mRNA and protein of AT2 and Bcl-2 in cardiomyocytes, methods of terminal-deoxynucltidyl transferase mediated nick end labeling (TUNEL), reversal transcription polymerase chain reaction (RT-PCR) and immunoblot (Western Blot) were used, respectively. RESULTS: Values of -dp/dt(max) in exp1, exp2 or con2 were much less than those in con1, respectively (p < 0.01). CAI (= stained cell number/total cell number x 100%) and AT2 values both in mRNA and protein levels in con1 were less than those in the other three groups, respectively (p < 0.01). The three parameters above were more in exp1 but less in exp2 than those in con2, respectively (p < 0.01). The three parameters and HW in exp1 were much higher than those in exp2, respectively (p < 0.01). Changes of Bcl-2 were opposed to those of AT2. CONCLUSIONS: A high expression of AT2 may accelerate the apoptosis of cardiomyocytes in diabetic rats and play a role in precipitating diabetic cardiomyopathy; taurine may protect diabetic rats from developing cardiomyopathy also by downregulating AT2 receptors.

Effects of Ginkgo leaf extract on function of dendritic cells and Th1/Th2 cytokines in patients with unstable angina pectoris.

OBJECTIVE: To investigate the effects of Ginkgo leaf extract (GLE) on function of dendritic cells (DC) and Th1/Th2 cytokines in patients with unstable angina pectoris (UAP). METHODS: Fifty-four patients with UAP were equally assigned into two groups, the treated group and the control group, both treated with conventional Western medicine, but with GLE given additionally to the treated group. Blood of all patients was taken before and 4 weeks after treatment to prepare the peripheral mononuclear cells, then which were incubated in the completed medium containing granulocyte-macrophage colony stimulatory factor (GM-CSF) and interleukin-4 (IL-4) to induce mature DC. The expression of co-stimulating factor CD86 (B7-2) on the surface of DC was detected by flow cytometry, and the stimulating capacity of DC was determined by mixed lymphocyte reaction (MLR). The blood levels of cytokines, interferon-gamma (IFN-gamma), and IL-4, were analyzed by ELISA, and blood C-reactive protein (CRP) level by turbidimetry. Moreover, the direct effect of Ginkgolide B on CD86 expression on DC were also tested in vitro. RESULTS: After treatment, CD86 expression on DC, the stimulating capacity of DC as well as levels of IFN-gamma and CRP were lowered in both groups (P < 0.05 or P < 0.01), but the changes were much more significant in the treated group than those in the control group. Ginkgolide B showed a direct inhibitory effect on the CD86 expression on DC. CONCLUSION: The inhibition of GLE on DC and thereby the suppression on inflammatory reaction may be one of the mechanisms of GLE in treating patients with UAP.