Nitish Naik

A Comparison of Lead Placement Through the Subclavian Vein Technique With Fluoroscopy-Guided Axillary Vein Technique for Permanent Pacemaker Insertion

BACKGROUND The intrathoracic subclavian venous technique for pacemaker implantation may be associated with serious complications. We describe an alternative technique for obtaining venous access for pacemaker implantation through axillary vein under fluoroscopic guidance and compare it with the conventional, subclavian approach. METHODS We conducted a single-centre, prospective, nonrandomized study. All adult patients with indication for permanent pacing who consented were recruited during a 3-year period. To access the axillary vein, we used the alternative technique with a new fluoroscopic landmark. The subclavian access was obtained as per the usual approach. RESULTS We studied 478 lead placements during 3 years; 315 lead placements through axillary venous technique (group 1) were compared with 163 lead placements through subclavian venous technique (group 2). Both routes had a high and comparable success rate, 98.09% in group 1 and 96.93% in group 2. The axillary approach was successful at the first attempt in 194 punctures (61.6%), as vs 60 in group 2 (36.8%) P < 0.0001. The average number of attempts in group 1 was 2.06 per patient and 2.56 in group 2 (P < 0.001). There were 3 (2.94%) pneumothoraxes in group 2 and none in group 1. During a mean follow-up period of 3.2 months in group1 and 3.7 months in group 2, 1 patient in group 2 had a lead fracture. CONCLUSIONS The fluoroscopically guided axillary venous approach for implanting permanent pacemakers is equivalent to the traditional anatomic landmark-guided intrathoracic subclavian approach and has fewer complications and shorter procedural time to access the vein.

Quantitative assessment of cardiac mechanical dyssynchrony and prediction of response to cardiac resynchronization therapy in patients with nonischaemic dilated cardiomyopathy using gated myocardial perfusion SPECT.

ObjectiveThe aim of the study was to evaluate gated myocardial perfusion SPECT (GMPS) in the prediction of response to cardiac resynchronization therapy (CRT) in nonischaemic dilated cardiomyopathy patients. Patients and methodsThirty-two patients (23 men, mean age 57.5±12.1 years) with severe heart failure, who were selected for CRT implantation, were prospectively included in this study. Patients with coronary heart disease and structural heart diseases were excluded. 99mTc-MIBI GMPS and clinical evaluation were performed at baseline and 3 months after CRT implantation. In GMPS, first-harmonic fast Fourier transform was used to extract a phase array using commercially available software. Phase standard deviation (PSD) and phase histogram bandwidth (PHB) were used to quantify cardiac mechanical dyssynchrony (CMD). Left ventricular ejection fraction was evaluated. ResultsAt baseline evaluation the mean NYHA class was 3.3±0.5, left ventricular ejection fraction was 23.2±5.3% and mean QRS duration was 150.3±18.2 ms. PSD was 55.8±19.2° and PHB was 182.1±75.8°. At 3-month follow-up, 22 patients responded to CRT with improvement in NYHA class by more than 1 grade and in ejection fraction by more than 5%. Responders had significantly larger PSD (63.6±16.6 vs. 38.7±12.7°) and PHB (214.8±63.9 vs. 110.2±43.5°) compared with nonresponders. Receiver-operating characteristic curve analysis demonstrated 86% sensitivity and 80% specificity at a cutoff value of 43° for PSD and 86% sensitivity and 80% specificity at a cutoff value of 128° for PHB in the prediction of response to CRT. ConclusionBaseline PSD and PHB derived from GMPS are useful for prediction of response to CRT in nonischaemic dilated cardiomyopathy patients.

Mesoaortic entrapment of a left inferior vena cava

A persistent left inferior vena cava (IVC) is a rare anomaly, with a reported incidence of only 0.2-0.5%. When present, it courses between the superior mesenteric artery and the aorta to continue as the right IVC, similar to the course of a left renal vein (LRV). This anomaly is usually asymptomatic, but there may be vague abdominal complaints if the IVC is compressed in the mesoaortic angle. Although symptomatic compression of the LRV (anterior nutcracker syndrome) is well recognized, there has been only one report in the literature of a similar compression of a persistent left IVC. Because of its rarity, this anomaly may be missed or mistaken for other conditions on imaging. An accurate diagnosis is crucial as the presence of this anomaly may have implications for surgical treatment of aortic lesions or placement of an IVC filter. Magnetic resonance angiography and, more recently, multidetector computed tomography scan, can provide an exquisite three-dimensional demonstration of vascular abnormalities.

Acute electrocardiographic changes during smoking: an observational study

Objective To study the temporal relationship of smoking with electrophysiological changes. Design Prospective observational study. Setting Tertiary cardiac center. Participants Male smokers with atypical chest pain were screened with a treadmill exercise test (TMT). A total of 31 such patients aged 49.8±10.5 years, in whom TMT was either negative or mildly positive were included. Heart rate variability (HRV) parameters of smokers were compared to those of 15 healthy non-smoking participants. Interventions All patients underwent a 24 h Holter monitoring to assess ECG changes during smoking periods. Results Heart rate increased acutely during smoking. Mean heart rate increased from 83.8±13.7 bpm 10 min before smoking, to 90.5±16.4 bpm during smoking, (p<0.0001) and returned to baseline after 30 min. Smoking was also associated with increased ectopic beats (mean of 5.3/h prior to smoking to 9.8/h during smoking to 11.3/h during the hour after smoking; p<0.001). Three patients (9.7%) had significant ST–T changes after smoking. HRV index significantly decreased in smokers (15.2±5.3) as compared to non-smoking controls participants (19.4±3.6; p=0.02), but the other spectral HRV parameters were comparable. Conclusions Heart rate and ectopic beats increase acutely following smoking. Ischaemic ST–T changes were also detected during smoking. Spectral parameters of HRV analysis of smokers remained in normal limits, but more importantly geometrical parameter—HRV index—showed significant abnormality.

Prevalence of metabolic syndrome and cardiovascular changes in patients with chronic plaque psoriasis and their correlation with disease severity: A hospital-based cross-sectional study

Background: Previous epidemiological studies suggest an association between psoriasis and metabolic syndrome and risk of subclinical atherosclerosis. However, there is a paucity of data in the Indian population on these associations. Objectives: To evaluate the prevalence of metabolic syndrome and subclinical atherosclerosis in patients with chronic plaque psoriasis compared to healthy controls and to correlate the prevalence of metabolic syndrome with severity of psoriasis. Methods: A hospital-based cross-sectional study was performed on 140 patients with chronic plaque psoriasis and 140 controls. Psoriasis was categorized as mild, moderate and severe based on psoriasis area and severity index (<10, 10–14 and ≥15, respectively) and as disease of short (<1 year), intermediate (1–3 years) and long duration (>3 years). In all patients and controls, body mass index was calculated, blood pressure and waist circumference were measured and fasting bloaod sugar and lipid profile were estimated. Metabolic syndrome was diagnosed by the presence of 3 or more of the modified National Cholesterol Education Programs Adult Treatment Panel III criteria. A subset of 30 psoriatic patients and 30 healthy controls were selected by the systematic sampling method for cardiac evaluation including electrocardiography, echocardiography and carotid intima-media thickness measurement. Results: The prevalence of metabolic syndrome was significantly more in psoriatic patients than in controls (39.3% vs. 17.1%, odds ratio = 3.13). Psoriatic patients also had a significantly higher prevalence of hypertension, abdominal obesity and diabetes. There was a significant trend to increase in prevalence of metabolic syndrome, hypertension and type 2 diabetes with increased severity and longer duration of the psoriasis. Patients with psoriasis had significantly higher carotid intima-media thickness (mean 0.61 mm ± 0.01 mm vs. 0.37 mm ± 0.01 mm) than controls. Limitation: This was a hospital-based cross-sectional study with a relatively small sample size. A prospective study with a larger sample would have validated the results further. Conclusion: There is a significantly higher prevalence of metabolic syndrome in psoriasis patients as compared to controls; the prevalence of metabolic syndrome and its components increases with severity and duration of psoriasis. There is a higher prevalence of subclinical atherosclerosis in patients with psoriasis thus increasing the risk of cardiovascular disease. We suggest that patients with moderate to severe psoriasis be screened routinely for metabolic syndrome and cardiovascular disease and encouraged to correct modifiable cardiovascular risk factors.

Malignant idiopathic ventricular fibrillation "cured" by radiofrequency ablation.

Idiopathic Ventricular Fibrillation is a rare cause of sudden cardiac death. It may be difficult to prospectively diagnose idiopathic ventricular fibrillation due to the episodic nature of the arrhythmias as well as the inability to induce the clinical tachycardia on electrophysiological studies. Although an implantable cardioverter defibrillator can terminate episodes of ventricular fibrillation, it cannot prevent recurrences. We describe a patient who underwent radiofrequency ablation of the culprit ectopics initiating ventricular fibrillation for frequent symptomatic episodes.

The increasing burden of diabetes and variations among the states of India: the Global Burden of Disease Study 1990–2016

Summary Background The burden of diabetes is increasing rapidly in India but a systematic understanding of its distribution and time trends is not available for every state of India. We present a comprehensive analysis of the time trends and heterogeneity in the distribution of diabetes burden across all states of India between 1990 and 2016. Methods We analysed the prevalence and disability-adjusted life-years (DALYs) of diabetes in the states of India from 1990 to 2016 using all available data sources that could be accessed as part of the Global Burden of Diseases, Injuries, and Risk Factors Study 2016, and assessed heterogeneity across the states. The states were placed in four groups based on epidemiological transition level (ETL), defined on the basis of the ratio of DALYs from communicable diseases to those from non-communicable diseases and injuries combined, with a low ratio denoting high ETL and vice versa. We assessed the contribution of risk factors to diabetes DALYs and the relation of overweight (body-mass index 25 kg/m2 or more) with diabetes prevalence. We calculated 95% uncertainty intervals (UIs) for the point estimates. Findings The number of people with diabetes in India increased from 26·0 million (95% UI 23·4–28·6) in 1990 to 65·0 million (58·7–71·1) in 2016. The prevalence of diabetes in adults aged 20 years or older in India increased from 5·5% (4·9–6·1) in 1990 to 7·7% (6·9–8·4) in 2016. The prevalence in 2016 was highest in Tamil Nadu and Kerala (high ETL) and Delhi (higher-middle ETL), followed by Punjab and Goa (high ETL) and Karnataka (higher-middle ETL). The age-standardised DALY rate for diabetes increased in India by 39·6% (32·1–46·7) from 1990 to 2016, which was the highest increase among major non-communicable diseases. The age-standardised diabetes prevalence and DALYs increased in every state, with the percentage increase among the highest in several states in the low and lower-middle ETL state groups. The most important risk factor for diabetes in India was overweight to which 36·0% (22·6–49·2) of the diabetes DALYs in 2016 could be attributed. The prevalence of overweight in adults in India increased from 9·0% (8·7–9·3) in 1990 to 20·4% (19·9–20·8) in 2016; this prevalence increased in every state of the country. For every 100 overweight adults aged 20 years or older in India, there were 38 adults (34–42) with diabetes, compared with the global average of 19 adults (17–21) in 2016. Interpretation The increase in health loss from diabetes since 1990 in India is the highest among major non-communicable diseases. With this increase observed in every state of the country, and the relative rate of increase highest in several less developed low ETL states, policy action that takes these state-level differences into account is needed urgently to control this potentially explosive public health situation. Funding Bill & Melinda Gates Foundation; and Indian Council of Medical Research, Department of Health Research, Ministry of Health and Family Welfare, Government of India.

Normal values of cardiac mechanical synchrony parameters using gated myocardial perfusion single-photon emission computed tomography: Impact of population and study protocol

Purpose of the Study: Normal values of cardiac mechanical synchrony parameters in gated myocardial perfusion single-photon emission computed tomography (GMPS) are well established in literature from the Western population. The aim of the study is to establish normal values of mechanical synchrony with GMPS in Indian population and to find out whether it differs significantly from established values. Procedure: We retrospectively analyzed 1 day low-dose stress/high-dose rest GMPS studies of 120 patients (sixty males, 52 ± 11.7 years) with low pretest likelihood of coronary artery disease and having normal GMPS study. In GMPS, first-harmonic fast Fourier transform was used to extract a phase array using commercially available software. Phase standard deviation (PSD) and phase histogram bandwidth (PHB) were used to quantify cardiac mechanical dyssynchrony. Results: The values obtained were as follows, PSD: In men, 14.3 ± 4.7 (stress) and 8.9 ± 2.9 (rest), in women 11 ± 4 (stress) and 7.7 ± 2.7 (rest), and PHB: In men, 40.1 ± 11.9 (stress) and 30.6 ± 7.6 (rest), in women, 34.7 ± 12.6 (stress) and 25.3 ± 8.6 (rest). The value of PSD and PHB was significantly less in Indian population as compared with established values in literature. We also observed that synchrony indices derived from the low-dose stress studies are higher than high-dose rest studies. Conclusions: The value of synchrony parameters differs significantly according to population and methodology suggesting that specific population and methodology-based normal database for assessment of cardiac mechanical dyssynchrony should be established.

Evaluation of early direct current cardioversion for maintenance of sinus rhythm in rheumatic atrial fibrillation following successful balloon mitral valvotomy.

Background Patients with rheumatic mitral stenosis (MS) and atrial fibrillation (AF) are at risk for thromboembolism and restoration of sinus rhythm (SR) may be the preferred strategy. Percutaneous balloon mitral valvotomy (PBMV) improves hemodynamics, but may not be enough to restore SR. Methods Prospective randomized study aimed at evaluating efficacy of early direct current cardioversion (DCCV) following successful PBMV in patients with long-standing AF. Group 1 (n = 20) had patients of rheumatic MS with AF who underwent successful PBMV. Group 2 (n = 15) patients were DC cardioverted and administered oral Amiodarone for 6 weeks. Primary endpoint was maintenance of SR after 6 months. Secondary endpoints were functional capacity, number of embolic episodes, adverse drug effects, and all-cause mortality. Results In Group 2, all patients underwent successful cardioversion. At a mean follow-up of 7.6 months, 95% in Group 1 were in AF. In Group 2, 87% patients were in SR and 13% had reverted to AF. Difference in rate of SR was 0.82 (95% CI 0.2, 1.01) (p = 0.001), with relative risk of 7.1 (1.95, 25.9, 95% CI, p = 0.001) for patients to be in AF who underwent only successful PBMV, i.e. Group 1. There was significant improvement in quality of life (SF36) score in Group 2 (p = 0.001), with no deaths, stroke, or adverse drug effects in either group. Conclusion In patients with rheumatic MS and AF, early DCCV and a short-duration oral Amiodarone, following successful PBMV, may be a reasonable strategy to attain long-term SR.

Paced QRS duration predicts left ventricular function in patients with permanent pacemakers - One-year follow-up study using equilibrium radionuclide angiography (ERNA).

Summary Permanent pacing, being non physiological, often results in ventricular dysfunction over time. Narrower paced QRS duration from pacing the right ventricular outflow tract septum, might result in relatively preserved ventricular function over long term follow up.