Latest news with #GregoryMarcus
Medscape
5 days ago
- Health
- Medscape
Post-Ablation Visual Auras a Sign of Transient Brain Injury?
Catheter ablation procedures involving transseptal puncture — typically used to treat atrial fibrillation — are often linked to migraine-like visual auras, though the underlying cause has been unclear. New evidence suggests these auras may stem not from the puncture itself but from acute, procedure-related brain emboli affecting the visual cortex. Gregory Marcus, MD, MAS 'These research findings have two distinct clinically relevant implications,' senior author Gregory Marcus, MD, MAS, cardiac electrophysiologist and endowed professor of atrial fibrillation research, University of California San Francisco (UCSF), told Medscape Medical News . 'First, they suggest that migraine symptoms with visual auras are less likely to be due to shunting of some neuroactive compound across interatrial septal defects and more likely occur as a result of occlusion of blood flow due to brain emboli,' Marcus said. 'Second, these findings demonstrate that, contrary to a long-held belief that these post-ablation MRI-detected small brain lesions are asymptomatic — in fact, they are often referred to as 'asymptomatic cerebral emboli' or 'ACEs' — these small acute brain lesions actually can, and perhaps often do, manifest in clinical symptoms,' he added. 'This finding could change the whole paradigm of treatment, perhaps focusing more on prevention of blood clots,' he added in a statement. The study was published online on July 7 in the journal Heart Rhythm . Brain Injury From Catheter Ablation? The TRAVERSE trial enrolled 146 adults undergoing catheter ablation for ventricular arrhythmias; 74 were randomly allocated to ventricular access via transeptal puncture (creating a new, temporary hole between the left and right atria) and 72 to a retrograde approach (through the aortic valve, not requiring transseptal puncture). All patients underwent high-resolution brain MRI the day after ablation and 63 (85%) in the transseptal group and 57 (79%) in the retrograde group completed a validated migraine questionnaire, a median of 38 days after the procedure. There was no difference in post-ablation visual auras between the transseptal and retrograde aortic approaches (16% and 14%, respectively). However, significantly more patients with acute brain emboli in the occipital or parietal lobes reported migraine-related visual auras (38% vs 11%; P < .01). After multivariable adjustment, the presence of acute brain emboli in the occipital or parietal lobes was associated with a 12-fold greater likelihood of visual auras. The data show that these post-ablation brain lesions are not 'clinically silent,' first author Adi Elias, MD, cardiac electrophysiology fellow at UCSF, noted in the statement. 'It may be the case that we haven't known what to look for and assessed for symptoms immediately without enough time for the subsequent visual auras that would occur,' Elias said. Marcus elaborated on this point. He noted that prior studies have demonstrated that these small post-catheter ablation MRI-detected lesions can no longer be detected upon repeat imaging about a month later, demonstrating that the ability to detect these brain emboli is fleeting. 'Prior studies failed to demonstrate a relationship between migraine with visual aura and acute brain emboli, but perhaps they were too late to detect ephemeral MRI findings because the MRI had to be ordered and performed after symptoms develop,' Marcus said. The TRAVERSE study is 'unique in that everyone had a brain MRI immediately after their catheter ablation procedure and likely in most, if not all cases, prior to the development of their visual aura symptoms,' he noted. Importantly, said the researchers, the presence of brain emboli and visual auras was not associated with any significant change in cognition. Marcus said patients can be reassured that procedure-related brain emboli and visual auras typically fade within a month of the procedure. An Under-Recognized Condition Reached for comment, Mina Chung, MD, president of the Heart Rhythm Society, who wasn't involved in the study, told Medscape Medical News the occurrence of visual auras after ablation may be 'under-recognized.' The fact that a prior history of visual auras was associated with visual auras at 1 month after the procedure, 'suggests some preexisting tendency toward such symptoms after these procedures,' said Chung, with the Department of Cardiovascular Medicine, Heart, Vascular, and Thoracic Institute, Cleveland Clinic, Cleveland. 'Reassuringly, there were no detectable differences in neurocognitive function,' said Chung.
Medscape
03-07-2025
- Health
- Medscape
Elite Rowers Face Lasting Atrial Fibrillation Risk
Former world-class rowers have an elevated risk for atrial fibrillation (AF) in the years after retirement, according to an observational case-control study. Researchers found 1 in 5 former Olympic, world, or national-level Australian rowers aged 45-80 years had the heart rhythm anomaly. The ex-rowers, who had competed for at least 10 years, were nearly seven times more likely to have been diagnosed with AF compared to a control group. During a follow-up period of around 4 years, new cases of AF were also higher among the ex-rowers (6.3% vs 2.3%), according to the researchers, who published their findings last month in the European Heart Journal . 'As a clinician, I was not surprised that rowers experienced more AF,' said André La Gerche, PhD, MD, a cardiologist and head of the Heart Exercise And Research Trials Lab at the Victor Chang Cardiac Research Institute and St Vincent's Hospital in Melbourne, Australia, and senior author of the study. 'However, I was very surprised by the magnitude of the difference. Furthermore, I learnt that the risk persists years after retirement and is not just due to genetic factors.' André La Gerche, PhD, MD The findings are 'consistent with prior research demonstrating that endurance athletes — especially highly trained endurance athletes — seem to have this higher risk of AF,' said Gregory Marcus, MD, MAS, a cardiac electrophysiologist and the inaugural Endowed Professor of Atrial Fibrillation Research at the University of California, San Francisco. Gregory Marcus, MD, MAS 'These numbers nudge me in the direction of more aggressively screening for AF specifically in masters-aged rowers, such as with the use of Holter monitors or wearable devices approved to detect AF,' said Jeffrey Hsu, MD, an assistant professor of medicine in the Division of Cardiology at the David Geffen School of Medicine at the University of California, Los Angeles. Jeffrey Hsu, MD La Gerche and his team captured data from 121 former rowers — 75% men, all White, with a median age of 62 years — who were matched with more than 11,000 control individuals from the UK Biobank who had never rowed and had varying fitness levels. The ex-rowers had similar rates of ischemic heart disease and diabetes as did the control individuals, but lower blood pressure. They also were less likely to have ever smoked. The athletes showed persistent changes in cardiac function after retirement. Ex-rowers had larger left ventricles, lower heart rates, longer PQ intervals, and longer QT intervals compared to control individuals. The research, 'raises the question of whether certain types of intensive exercise — like elite-level competitive rowing — leads to long-lasting, perhaps even irreversible, enlargement of the cardiac chambers,' Hsu said. Genetics factored into the risk for AF among both groups. While the prevalence of rare variants in genes associated with cardiomyopathy was low across the study, the combined risk for individual genes associated with AF was a strong predictor of the disease in both athletes (odds ratio [OR], 3.7) and nonathletes (OR, 2.0). The proportions were similar between them ( P = .37), indicating genetics did not fully account for the increased risk in the ex-rowers, La Gerche said. Marcus flagged a few factors that may have skewed the results. The former athletes tended to be tall, White, and in many cases, drank more alcohol than control individuals — all of these factors increase the risk for AF. Because the ex-rowers volunteered for a cardiovascular study, selection bias could have skewed prevalence higher, Marcus said. After a sensitivity analysis, ex-rowers still had a 2.5-fold higher risk for AF in the case of a 100% selection bias. La Gerche emphasized the findings shouldn't dissuade clinicians from encouraging regular exercise or high-level sports training. 'The overall health outcomes of these rowers are generally superb,' La Gerche said. 'Rather, this highlights an important 'Achilles heel' that requires attention and, ideally, effective prevention strategies so that sports can be enjoyed by more people, more often.' The study was funded by the National Health and Medical Research Council. La Gerche, Hsu, and Marcus reported having no relevant financial conflicts of interest.
