Transcatheter aortic valve replacement in the developing world: Lessons learnt and its implications for practice.

Backrground: Transcatheter aortic valve replacement (TAVR) has become an accepted modality of treatment in intermediate and high surgical risk patients of symptomatic severe calcific aortic stenosis (AS). We herein report Indian data of 84 intermediate and high-risk patients who underwent TAVR at two Armed Forces cardiac centres. Methods: Most of the patients underwent TAVR in cardiac catheterization lab by percutaneous transfemoral approach, under conscious sedation. Patients were followed up and echocardiographic parameters were assessed after six months of procedure. Results: Total of 84 intermediate and high-risk patients underwent TAVR between Jan 2017 and June 2021. Mean age of population was 71.5 ± 8.4 years; 28.5% of patients had bicuspid aortic valve and Mean STS score was 6.34 ± 2.08. Majority (92.8%) patients underwent the procedure under conscious sedation. Self-expanding valves were used in 72.6% and balloon expandable in 27.4% of patients. Predilatation was done in 64% patients while 13% cases underwent post dilatation. Procedural mortality was 2.3%. Rate of permanent pacemaker implantation was 4.9%. Ischemic stroke occurred in 1.1% of patents. There was no case of severe paravalvular leak. Emergency surgical aortic valve replacement was done in 2.4% patients. Procedural success in this study was 97.6%. All-cause mortality was 9.5% at 6 months. Conclusions: TAVR is an effective treatment modality in intermediate and high-risk Indian patients with severe aortic stenosis. Patients with bicuspid or previous bio prosthetic aortic valves also have a good outcome post TAVR.

Analysis of ST-elevation myocardial infarction occurring in soldiers during strenous military training.

BACKGROUND: At our tertiary care cardiology center, we are receiving soldiers who sustained acute ST-Elevation Myocardial Infarction (STEMI) during the strenuous Battle Field Efficiency Test (BPET) and other such activities. METHODS: This was a single-center observational study to assimilate and analyze the precipitating causes, risk factors, symptoms, and the efficacy of the management protocols in soldiers sustaining STEMI during the BPET or other forms of strenuous military training. RESULTS: All 25 soldiers with documented STEMI following strenuous military training presented with chest pain as the primary symptom. 88% had symptoms either during or within 1st hour of the strenuous activity. 76% underwent thrombolysis with an angiographic success rate of 95%. Primary PCI was possible in only 3/25 (12%) of the cases, of which 2 (66%) did not require stenting after thrombus aspiration; 88% of soldiers reported "training for the event" for less than four times/week. CONCLUSION: STEMI precipitated by strenuous unaccustomed military training have exclusively single vessel affection with an excellent response to thrombolysis and thrombus aspiration. Thus, the timely institution of pharmacological or mechanical revascularization therapy has dramatic results in the preservation of ventricular function. The lack of training for the strenuous event provides strong evidence for comprehensive, graded, physical training prior to strenuous military activities to prevent acute coronary syndromes.

Study of transesophageal echocardiography in young patients (<40 years) with acute arterial ischemic stroke: A pilot study.

BACKGROUND: The aim is to study cardiac abnormalities as detected by transesophageal echocardiography (TEE) in young patients (<40 years) presenting with acute ischemic arterial stroke. METHODS: A cross-sectional observational study was conducted in young patients aged <40 years presenting with acute arterial ischemic stroke without any valvular heart disease, prosthetic valve, or previously diagnosed atrial fibrillation (AF). TEE was performed in all eligible patients preferably within the first week of the onset of ischemic arterial stroke. All patients with normal TEE underwent holter to rule out paroxysmal AF. RESULTS: Totally, 40 young patients were included in the study. Mean age was 35.17 (SD [standard deviation] ± 2.99) years. TEE abnormalities were noted in total 13 (32.5%) patients, of which patent foramen ovale was the most common cardiac abnormality in eight (20%) patients followed by left atrial appendage clot in three (7.5%) and atrial septal aneurysm in two (5%) patients. One patient (2.5%) was observed with atrial septal aneurysm along with a sieved septum. All the patients with normal TEE underwent holter, and four of 27 (14.8%) of these patients were noted to have paroxysmal AF. CONCLUSION: Cardiac abnormalities on TEE and holter were detected in 42.5% of the young patients with idiopathic arterial stroke. TEE abnormality was noted in 33% (13/40), whereas AF on holter was seen in 14.8% (4/27) with normal TEE. Thus, probable cardioembolic stroke was responsible for acute ischemic stroke in 42.5% (17/40) of young patients in the absence of valvular heart disease, prosthetic valves, and persistent/permanent AF.

Profile of pulmonary embolism in service personnel posted at high altitude area.

BACKGROUND: We evaluated the clinical presentation and risk factors of pulmonary embolism (PE) in soldiers posted at high altitude areas (HAA). METHODS: We conducted a retrospective analysis of all cases of PE presented to us between March 2011 and Aug 2014. The patients were serving at an altitude between 10,000 and 22,000ft above sea level and PE was diagnosed using the pulmonary CT angiography. Screening for the deep vein thrombosis (DVT) and procoagulant conditions was done at presentation and after six months of treatment. The patients were managed as per the American College of Cardiology (ACC) guidelines and descriptive statistics were used to present the data. RESULTS: The patients (53 males) had a mean age of 33±4.2 year and were serving at a mean altitude of 12,176±448 feet (ranged between 10,000 and 20,500) at the onset of symptoms. Dyspnea (79%) and tachycardia (68%) were the commonest symptom and sign, respectively. D dimer was positive in 96.2% of the cases while nonspecific T inversion in the ECG was seen in 54.7% of the patients. Procoagulant work up revealed a hereditary thrombophilic condition in 9 out of 53 patients. A total of 44 cases were idiopathic and DVT of lower limb veins was seen in 2 patients. There was no mortality in our case series. CONCLUSION: PE is a common complication of HAA and hereditary thrombophilia contributes in a minority of the patients. Further studies are needed to ascertain the risk factors of PE at HAA.

Detection and localization of copy-paste forgeries in digital videos.

Amidst the continual march of technology, we find ourselves relying on digital videos to proffer visual evidence in several highly sensitive areas such as journalism, politics, civil and criminal litigation, and military and intelligence operations. However, despite being an indispensable source of information with high evidentiary value, digital videos are also extremely vulnerable to conscious manipulations. Therefore, in a situation where dependence on video evidence is unavoidable, it becomes crucial to authenticate the contents of this evidence before accepting them as an accurate depiction of reality. Digital videos can suffer from several kinds of manipulations, but perhaps, one of the most consequential forgeries is copy-paste forgery, which involves insertion/removal of objects into/from video frames. Copy-paste forgeries alter the information presented by the video scene, which has a direct effect on our basic understanding of what that scene represents, and so, from a forensic standpoint, the challenge of detecting such forgeries is especially significant. In this paper, we propose a sensor pattern noise based copy-paste detection scheme, which is an improved and forensically stronger version of an existing noise-residue based technique. We also study a demosaicing artifact based image forensic scheme to estimate the extent of its viability in the domain of video forensics. Furthermore, we suggest a simplistic clustering technique for the detection of copy-paste forgeries, and determine if it possess the capabilities desired of a viable and efficacious video forensic scheme. Finally, we validate these schemes on a set of realistically tampered MJPEG, MPEG-2, MPEG-4, and H.264/AVC encoded videos in a diverse experimental set-up by varying the strength of post-production re-compressions and transcodings, bitrates, and sizes of the tampered regions. Such an experimental set-up is representative of a neutral testing platform and simulates a real-world forgery scenario where the forensic investigator has no control over any of the variable parameters of the tampering process. When tested in such an experimental set-up, the four forensic schemes achieved varying levels of detection accuracies and exhibited different scopes of applicabilities. For videos compressed using QFs in the range 70-100, the existing noise residue based technique generated average detection accuracy in the range 64.5%-82.0%, while the proposed sensor pattern noise based scheme generated average accuracy in the range 89.9%-98.7%. For the aforementioned range of QFs, average accuracy rates achieved by the suggested clustering technique and the demosaicing artifact based approach were in the range 79.1%-90.1% and 83.2%-93.3%, respectively.

Risk factors for contrast-induced nephropathy after coronary angiography.

Contrast-induced nephropathy (CIN) is of concern after the use of radiocontrast media for coronary angiography (CAG) and percutaneous coronary intervention (PCI). We studied the incidence of CIN and its risk factors in patients undergoing CAG. In this prospective study, we included all patients with normal renal parameters undergoing CAG with nonionic radiocontrast media. We excluded patients with known chronic kidney disease, baseline creatinine more than 1.5 mg/dL, significant hypotension, anemia, and patients with acute myocardial infarction undergoing emergency PCI. Serum creatinine was done at baseline and serially for seven days after the procedure. Appropriate statistical tests were used to analyze the results and P <0.05 was considered statistically significant. The study population (n = 500, 348 males and 152 females) had a mean age of 56.6 ± 12.5 years. Twelve patients (2.4%) developed CIN and were equally distributed irrespective of the age, diabetes, or PCI procedure. CIN was observed to be more common in patients with hypertension than in those without hypertension (P = 0.0158). The total volume of contrast administered to CIN group (175 ± 59.3) was not significant as compared to that of non-CIN (159.1 ± 56) group (P = 0.334). None of the patients in our study required renal replacement therapy, and there was no mortality. CIN is observed in 2.4% of patients undergoing CAG and had a self-limiting course. Hypertension is the only observed risk factor, and further large-scale studies are necessary to delineate the novel risk factors for CIN in the general population with normal kidney function.

Dispersal ability and parasitisation performance of Trichogramma spp (Hymenoptera:Trichogrammatidae) in organic Basmati rice.

The dispersal/host searching capacity of Trichogramma chilonis Ishii and Trichogramma japonicum Ashmead was studied in organic Basmati rice during 2012 and 2013. Results showed that the level of parasitism was negatively correlated with the distance between host eggs and parasitoids' release point. Parasitisation rate was more (11.39-18.10% and 9.77-15.49% by T. chilonis and T. japonicum, respectively) near the release point (1-3m) with maximum parasitism at 1m by both the parasitoid species. A very low parasitism (0.05-0.47%) was recorded up to the distance of 8-9 m in two species. Among the two parasitoid species, T. chilonis showed higher parasitism (up to 18.10%) in different distance treatments in comparison to T. japonicum (up to 15.49%).

Thyroid and aging or the aging thyroid? An evidence-based analysis of the literature.

Thyroid hormone production, metabolism, and action change with aging. The reference ranges for serum thyrotropin and thyroid hormones are derived mainly from younger populations. Thus, the prevalence of subclinical thyroid dysfunction is increased greatly in the elderly. However, it is unclear whether mild thyroid dysfunction in the elderly is associated with adverse outcomes. In this review, we discuss current evidence-based literature on thyroid function in the elderly and whether subclinical thyroid dysfunction in the elderly should be treated.

Angioplasty of congenital pulmonary vein stenosis.

We present a unique case of idiopathic pulmonary vein stenosis in an adult who presented with progressive dyspnea and severe pulmonary arterial hypertension. Magnetic resonance imaging confirmed the diagnosis. The patient was treated by balloon angioplasty and is well at 6 months post-treatment follow-up. The etiology of pulmonary vein stenosis in this case is difficult to ascertain, but is likely to be congenital.

Large spontaneous coronary artery dissections-a study of three cases, literature review, and possible therapeutic strategies.

Spontaneous coronary artery dissection is rare, but is now being increasingly recognized as a prominent cause of acute ischemic coronary events occurring usually in relatively young patients, predominantly females. The authors describe the clinical course of 3 patients (1 woman) in whom large spontaneous coronary artery dissections developed. All had diverse clinical presentations;1 presenting with heart failure, the second with post-myocardial infarction angina, and the third with syncope. The second patient underwent coronary angioplasty with multiple overlapping stents while in the other two, it was the considered opinion to continue aggressive medical therapy. The 1-year follow-up was uneventful in all 3 patients. The risk factors ascertained in our patients were diabetes mellitus, smoking, and hypertension.

Pharmacotherapy of atrial fibrillation.

Atrial fibrillation is the most common sustained arrhythmia of clinical significance. Its prevalence rises with age. It is a significant cause of thromboembolic phenomena. We describe briefly the etiology and classification of atrial fibrillation, the risk factors for thromboembolism and stroke associated with it, the indications for hospitalization, and the therapeutic goal. We discuss in depth the management strategies for such patients and compare the impact of rate versus rhythm control in reducing morbidity and mortality attributed to arrhythmia, in light of past and present trials. A brief overview of the drugs used in the management of atrial fibrillation, their pharmacology and dosage, their effects and use in rhythm versus rate control with important side effects are also included. Finally, the prevention and treatment of thromboembolism in patients with atrial fibrillation, an important aspect of therapy, is revisited in light of recent advances.