Safety and Feasibility of Ultrasound-Guided Access for Coronary Interventions through Distal Left Radial Route.

Aims: Left distal transradial arterial approach (ldTRA) is a new interventional route that spares right radial artery (RRA) for use in haemodialysis and as bypass graft. Vasant Kunj Left dIstal Transradial ArtEry approach (VKLITE) study aimed to assess the feasibility and safety of ldTRA access during coronary angiography (CAG) and percutaneous coronary intervention (PCI). Methods and Results: Between April 2018 and June 2020, 108 patients were enrolled and underwent CAG ± PCI via ultrasound guided ldTRA. Arterial puncture, CAG, and PCI were successful in 96.3% (104/108), 92.1% (93/101), and 94.1% (32/34) patients, respectively. Access site crossover rate was 14/108 (13.0%). Mean puncture, procedure, and haemostasis time (minutes) were 6.7 ± 7.1, 55.7 ± 32.8, and 23.1 ± 11.9. Median total fluoroscopic time was 6.6 minutes (IQR-14.2), and median total radiation dose was 39.2 Gy-cm2 (IQR-97.0). Local haematoma occurred in 11 patients (10.2%) with major haematoma in 1.9%, all recovering within three weeks. Mean pain score was 2.4 ± 2.3, and patient satisfaction score was 9.0 ± 1.3. LdTRA access compared with RRA access (n = 121) showed significantly increased mean procedure time (55.7 ± 32.8 vs. 43.9 ± 26.0 minutes, p = 0.01) and median total fluoroscopic time (6.6 [IQR-14.2] vs. 4.7 [IQR-8.2] minutes, p = 0.02), with similar median total radiation dose (39.2 [IQR-97.0] vs. 43.8 [IQR-54.5] Gy-cm2, p = 0.56). No radial artery loss, dissection, pseudoaneurysm, arteriovenous fistula, or nerve injury was noted. Conclusions: LdTRA access is feasible with few complications during CAG/PCI. Patient comfort and satisfaction makes it a desirable route for coronary interventions.

Lipoprotein a - Lp(a).

Lp(a) is a genetically determined, heritable, independent and causal risk factor for ASCVD. About 1 in 5 people worldwide have elevated Lp(a) (>50 mg/dL or >125 nmol/L) whereas in Indians it is 25 %. Epidemiological, genome-wide association and mendelian randomization studies have demonstrated an association between elevated Lp(a) levels and increased incidence of myocardial infarction, aortic valve stenosis, ischemic stroke, heart failure, CV and all-cause mortality. The increased Lp(a)-mediated CV risk is mediated by pro-inflammatory, pro-thrombotic and pro-atherogenic processes, leading to progression of atherosclerosis and increased risk of thrombosis. Lp(a) level reaches peak by 5 years of age and remains stable over time. Levels are not much influenced by dietary and environmental factors but it can vary in certain clinical situations like thyroid diseases, chronic kidney disease, inflammation and sepsis. It should be measured at least once in life time. Cascade testing for high Lp(a) is recommended in the settings of FH, family history of (very) high Lp(a), and personal or family history of ASCVD. In the absence of specific Lp(a)-lowering therapies, comprehensive risk factor management is recommended as per guidelines for individuals with elevated Lp(a). PCSK9 inhibitors and Inclisiran reduce Lp(a) by 25%. Pelacarsen is an antisense oligonucleotide and is found to reduce Lp(a) by 80%. In a recent Indian study of 1,021 CAD patients, presence of elevated Lp(a) (>50 mg/dL) correlated with severe angiographic disease. 37% of ACS patients exhibited elevated Lp(a) and it was higher in young CAD patients with FH (43%).

CSI clinical practice guidelines for dyslipidemia management: Executive summary.

Dyslipidemias are the most important coronary artery disease (CAD) risk factor. Proper management of dyslipidemia is crucial to control the epidemic of premature CAD in India. Cardiological Society of India strived to develop consensus-based guidelines for better lipid management for CAD prevention and treatment. The executive summary provides a bird's eye-view of the 'CSI: Clinical Practice Guidelines for Dyslipidemia Management' published in this issue of the Indian Heart Journal. The summary is focused on the busy clinician and encourages evidence-based management of patients and high-risk individuals. The summary has serialized various aspects of lipid management including epidemiology and categorization of CAD risk. The focus is on management of specific dyslipidemias relevant to India-raised low density lipoprotein (LDL) cholesterol, non-high density lipoprotein cholesterol (non-HDL-C), apolipoproteins, triglycerides and lipoprotein(a). Drug therapies for lipid lowering (statins, non-statin drugs and other pharmaceutical agents) and lifestyle management (dietary interventions, physical activity and yoga) are summarized. Management of dyslipidemias in oft-neglected patient phenotypes-the elderly, young and children, and patients with comorbidities-stroke, peripheral arterial disease, kidney failure, posttransplant, HIV (Human immunodeficiency virus), Covid-19 and familial hypercholesterolemia is also presented. This consensus statement is based on major international guidelines (mainly European) and expert opinion of lipid management leaders from India with focus on the dictum: earlier the better, lower the better, longer the better and together the better. These consensus guidelines cannot replace the individual clinician judgement who remains the sole arbiter in management of the patient.

Fractional flow reserve: intracoronary versus intravenous adenosine induced maximal coronary hyperemia.

BACKGROUND: Fractional Flow Reserve (FFR), a measure of coronary stenosis severity is based on the achievement of maximal hyperemia of coronary microcirculation. The most widely used pharmacological agent is adenosine which is administered either by intra coronary or intra venous routes. IV route is time consuming, has more side effects and expensive. This study is undertaken to compare the two routes of administration. METHODS: FFR was assessed in 50 patients with 56 intermediate focal lesions using both IV and intracoronary (IC) adenosine. FFR was calculated as the ratio of the distal coronary pressure to the aortic pressure at maximal hyperemia. RESULTS: A total of 25 left anterior descending, 8 right, 21 circumflex, and 2 left main coronary arteries were evaluated. The mean percent stenosis was 63.91 ± 13.13 SD and, the mean FFR was 0.831 ± 0.0738 SD for IV and 0.832 ± 0.0707 SD for IC adenosine. There was a strong and linear correlation between 2 sets of observations with IV dose and IC adenosine dose (R = 0.964, y = 0.065 + 0.923x; p < 0.001) (y = IV dose, x = IC dose). The agreement between the two sets of measurements was also high, with a mean difference of: 0.001 ± 0.0197. The changes in heart rate and blood pressure were significantly higher in IV adenosine group. Different incremental doses were well tolerated, with fewer systemic adverse events with IC adenosine. Transient AV blocks were observed with both IV and IC adenosine. CONCLUSIONS: This study suggests that IC adenosine is equivalent to IV infusion for the determination of FFR. The administration of IC adenosine is easy to use, cost effective, safe and associated with fewer systemic events.

Angiographic follow-up of genous bioengineered stent in acute myocardial infarction (GENAMI)-a pilot study.

OBJECTIVE: GENAMI, an angiographic follow-up study was undertaken to evaluate the safety and efficacy of a new generation endothelial progenitor cell (EPC) capture stent, GENOUS during primary angioplasty for ST-elevation myocardial infarction (MI). METHODS: Eleven consecutive patients with acute ST-elevation MI underwent primary percutaneous coronary intervention (PCI) using a bio-engineered GENOUS EPC stent. RESULTS: Procedural success was 100%. Ten patients who survived underwent a follow-up angiography at 8 months. There was no instance of stent thrombosis during the follow-up period up to 12 months. The quantitative angiographic (quantitative coronary analysis [QCA]) follow-up data showed a late loss at 8 months of 0.97 +/- 0.94 mm and the late loss index was 44.35 +/- 40.47% with angiographic restenosis seen in 5 of 10 patients (50%). One of these patients with provocable ischemia underwent repeat PCI. CONCLUSIONS: The QCA data of this study shows a high late loss with frequent angiographic restenosis during follow-up with this stent during primary PCI for acute STEMI. This observation, with important clinical implications, needs to be confirmed in larger studies.

Mahaim automatic accelerated rhythm: a marker of successful radiofrequency ablation.

BACKGROUND: Mahaim pathways are characterized by the presence of an accessory pathway potential-the 'M' potential, at the tricuspid annulus. M potential is a very useful guide during radiofrequency ablation of Mahaim pathway. During ablation, an accelerated rhythm with ORS morphology, identical to fully pre-excited QRS complex is observed, and has been labeled as Mahaim automatic rhythm. We analyzed this rhythm during radiofrequency ablation of these pathways. METHODS AND RESULTS: Eighteen patients with Mahaim accessory pathways were taken up for electrophysiology study and radiofrequency ablation. Tricuspid annulus was mapped for 'M' potentials and targeted for ablation. Duration of ablation and number of ablation attempts were guided by Mahaim automatic rhythm during ablation. Mahaim tachycardia was inducible in all. 'M' potentials were recorded in 15/18 patients. Radiofrequency energy was delivered at the site where Mahaim accelerated rhythm was noticed and was continued till abolition of the rhythm. This resulted in long-term success. In 3 patients, M potentials were not recordable, and in them other methods including 3-dimensional electroanatomical mapping was also not successful. CONCLUSIONS: 'M' potential-guided radiofrequency ablation is a useful technique. Presence of Mahaim automatic rhythm and its abolition during ablation is associated with long-term success of the procedure.

Left atrial-coronary sinus dissociation following an attempt at radiofrequency ablation for a left lateral accessory pathway.

Coronary sinus electrograms generally represent the sequence of left atrial activation, and are very helpful in localizing and differentiating left lateral accessory pathway-mediated tachycardia from other supraventricular tachycardias. The activation of the coronary sinus from the left atrium occurs through muscle bridges, which may be discrete or form an intermingled continuum. These muscle bridges, if disconnected, may dissociate the coronary sinus from the left atrium, in which case the coronary sinus electrograms do not represent left atrial activation, and do not help to understand, or may cause misinterpretation of, the mechanism of supraventricular tachycardia. We report one such case of orthodromic supraventricular tachycardia mediated through the left lateral accessory pathway in which the coronary sinus got dissociated from the left atrium during radiofrequency ablation.

Pace mapping for the localization of focal atrial tachycardia arising near the mitral annulus.

Of the various therapeutic modalities available to treat ectopic atrial tachycardia, radiofrequency catheter ablation has shown excellent results. It is usually possible to localize the earliest site of endocardial activation by conventional or newer three-dimensional mapping techniques. We report a case of ectopic atrial tachycardia, wherein the tachycardia was being repeatedly interrupted by mechanical trauma. Finally, with the help of P wave pace mapping, the tachycardia was localized near the posterolateral part of the mitral annulus, and successfully ablated. This report demonstrates the utility of P wave pace mapping in ectopic atrial tachycardia.

Sildenafil in the management of primary pulmonary hypertension.

Primary pulmonary hypertension is a rare disorder of unknown etiology with a poor prognosis. There is no cure, and drug therapy is effective in only a few patients. Calcium-channel antagonists and anticoagulants are the mainstay of therapy. Prostacyclin therapy leads to significant clinical improvement but its use is restricted due to high cost and complex drug delivery systems. Sildenafil is a selective vasodilator and has been shown to be effective in decreasing pulmonary vascular resistance in animal models of pulmonary hypertension. We report the use of sildenafil in two patients of primary pulmonary hypertension who were refractory to conventional drug therapy.

Reversal of slow flow phenomenon during primary stenting by bail-out administration of abciximab.

BACKGROUND: Slow flow or no reflow phenomenon is increasingly being recognized as a serious problem during coronary angioplasty and stenting. This phenomenon is seen more often during angioplasty in highly thrombogenic milieux, especially in a setting of acute myocardial infarction. The treatment of this complication is often not satisfactory. In this study the authors assessed the efficacy of abciximab, a potent antiplatelet drug, in treating slow flow or no reflow phenomenon during primary percutaneous transluminal coronary angioplasty (PTCA) for acute myocardial infarction (AMI). METHODS: Twenty-one instances of persistent slow flow phenomenon were encountered in 131 consecutive patients subjected to primary PTCA for AMI (16%). It was more common in patients presenting with AMI complicated by cardiogenic shock (nine of 21, 43%). Of these 21 cases of slow flow, 10 patients were given injection abciximab during the procedure of primary PTCA as a bail-out measure after encountering the complication of slow flow or no reflow. A pre-discharge coronary angiography was carried out in all patients who survived. RESULTS: In seven of 10 patients in the abciximab group flow had improved to TIMI-3. In contrast, in the non-abciximab group TIMI flow improved in only four of 11 patients. Patients with persistent slow flow had significantly higher mortality at the first 30-day follow-up than patients with TIMI-3 flow (33% versus 1.8%, p<0.001). CONCLUSION: In this small nonrandomized study significant improvement in coronary flow was achieved by using intravenous abciximab after observing slow flow or no reflow phenomenon during primary PTCA. More frequent use of this drug in this milieu might help in preventing the development of this complication. Larger studies are warranted to confirm this life-saving beneficial effect of bail-out administration of abciximab during primary angioplasty.

Platelet glycoprotein IIb/IIIa inhibition using eptifibatide with primary coronary stenting for acute myocardial infarction: a 30-day follow-up study.

The results of primary coronary stenting for acute myocardial infarction (AMI) have been reported to improve significantly with the concomitant administration of platelet glycoprotein IIb/IIIa inhibitor abciximab. There are, however, no data available with the use of eptifibatide, a more cost-effective, small-molecule GP IIb/IIIa blocker with a shorter half-life. In a prospective multicenter feasibility and efficacy study, we assigned 55 consecutive patients with AMI being taken up for primary stenting to receive eptifibatide just before the procedure (two boluses of 180 microg/kg 10 min apart and a 24-hr infusion of 2 microg/kg/min). Clinical outcomes were evaluated at 30 days after the procedure. The angiographic patency of the vessel with TIMI flow rates, TIMI myocardial perfusion (TMP) grade, and corrected TIMI frame counts were assessed at the end of procedure and before hospital discharge. At 30 days, the primary endpoint, a composite of death, myocardial infarction, and urgent target vessel revascularization (TVR) was seen in 12.7% of patients. The TIMI 3 and TMP grade 3 flow, which was seen in 93% and 86% of patient, respectively, at the end of the procedure, declined to 86% and 78%, respectively (P < 0.05) before hospital discharge. Corrected TIMI frame counts also decreased from 25.7 +/- 7.2 to 22.9 +/- 6.8 (P < 0.05). There were five (9.1%) instances of subacute thrombosis (SAT) presenting as AMI, needing urgent TVR in all, within 3-5 days of the primary procedure. No excessive bleeding complication, directly attributable to the use of eptifibatide, was observed. The study was terminated prematurely because of an unacceptable SAT rate. Administration of eptifibatide along with primary stenting for AMI is associated with a high TIMI 3 and TMP grade 3 flow acutely. However, these flows decline significantly before hospital discharge and lead to a high rate of SAT. The dosage and duration of infusion of eptifibatide in this setting needs further evaluation.