Early and late syncope: understanding the mechanisms

Bearing in mind that:

The most common cause of syncope is vasovagal (VVS), followed by orthostatic hypotension (OH) and cardiac causes, (1)

The tilt test is the study used for the diagnosis of VVS and OH, being recommended (class IIa, level of evidence B) in those cases with suspected reflex cause, OH, postural orthostatic tachycardia syndrome or psychogenic syncope (PS) after “initial assessment” (interrogation, physical examination including orthostatic blood pressure test and 12-lead ECG) did not identify the cause of the syncope (“unexplained syncope”) (1)

Epidemiological studies have shown a “bimodal” distribution of this symptom, with a peak between 15-20 years and another after 70, (2-4)

The etiology of syncope differs with age: most young people will have VVS, while OH and cardiac causes tend to be more prevalent in older adults, (2, 5)

Diagnosis is often challenging in older adults because prodromes tend to be short-lived or absent and possible amnesia for a loss of consciousness event, which may therefore mask your diagnosis as just a blackout. a “fall” (3, 6, 7)

• “Unexplained syncope” is associated with a poor prognosis, with increased mortality and increased cardiovascular morbidity (8),

Torabi P. et al. (9) propose in this work the need to know the causes of “unexplained syncope” in different age groups and the factors associated with a “final diagnosis” to establish effective diagnostic approaches.

As the “age of onset” of syncope has only been investigated in certain populations (e.g. it is a bimodal pattern of “first episode” age and the influence of “early” (<30 years) vs. “late” (≥60 years) onset years of this symptom on the clinical features and the “final diagnosis”.

After ruling out cardiac causes of syncope and non-traumatic causes of loss of consciousness (eg, epilepsy), 1,972 patients with “unexplained syncope” were evaluated between 2008 and 2018 in a syncope unit of a tertiary hospital. The “final diagnoses” after the tilt test were: VVS, HO, hypersensitivity/carotid sinus disease (HSC/CAD), complex syncope (2 or more diagnoses), non-diagnostic tilt test (TTND) and SP. Patients with TTND were recommended for further evaluation to rule out cardiac and non-cardiac causes of syncope and epilepsy. Finally, 1928 patients with available data on “age at first episode” were included in the analysis, comparing clinical features and “final diagnosis” in 3 groups according to age at onset: “early” (<30 years), 30 -59 years and “late” (≥60 years).

The first finding of this study was that the “age” of the “first episode of syncope” also shows a “bimodal” distribution in this patient population, with a first peak at 15 years and the second, less pronounced, at 70. assessment” peaked at its highest at age 75, followed by a lowest at age 20.

Clinical features and “final diagnosis” were different according to “age at first episode” (early vs. late). A significantly higher frequency of prodromes (64% vs 26%), palpitations (41% vs 15%), VVS (59% vs 19%) and SP (4% vs 0.2%) were observed in those with a first ‘early’ episode compared to those who had it “delayed.” In contrast, HO (23% vs 3%), HAC/ESC (9% vs 0.6%) and complex syncope (26% vs 14%) were significantly more frequent in those with a “late” first episode, compared to those who had it “early”. No significant differences were observed in the frequency of TTND between the 2 groups (initial 19% and late 23%).

Table 1: Clinical characteristics and diagnostic result of the tilt test with “first episode of syncope” <30 (“early”) and ≥60 years (“late”).

Results are expressed as a number (percentage), except * which are expressed as a median (interquartiles). HT: high blood pressure. VSV: vasovagal syncope. OH: orthostatic hypotension. CAH/ESC: carotid sinus hypersensitivity/disease. PP: psychogenic syncope. TTND: non-diagnostic tilt test

In the subgroup of 836 patients who were evaluated for syncope after age 60 years (Table 2), only 12% reported an “early” episode. The majority (70%) had their first “delayed” episode. VVS was significantly more frequent in those with an “early” first episode (39% vs 19%), while OH was significantly more frequent in those with a “late” onset (23% vs 7%). Prodromes were significantly less frequent in those with a “late” first episode (26% vs 52%). A “late” first episode was a predictor of HO and HAC/ESC (+31% and +26%, respectively, for every 10-year difference). In contrast, an “early” first episode was the occurrence of prodromes, VLS and complex syncope (+23%, +22% and +9% respectively, for each 10-year difference). Table 3.

Table 2: Clinical features and diagnostic result of the tilt test in patients aged ≥60 years at the time of evaluation.

Results are expressed as a number (percentage), except * which are expressed as a median (interquartiles). HTA: high blood pressure. VSV: vasovagal syncope. OH: orthostatic hypotension. HSC/ESC: carotid sinus hypersensitivity/disease. PP: psychogenic syncope. TTND: non-diagnostic tilt test

Table 3: Association between “final diagnosis” of syncope according to “age at first episode”: “early” (<30) vs “late” (≥60 years)

* OR: Probability ratios presented by 10-year increments in “age at first episode” of syncope

Although the large number of patients included is highlighted as strengths of this study, the authors mention as potential limitations of being a single-center study, the potential bias of including a selected population referred to a syncope unit to perform the tilt test, and the possible error in the determination of a clinical variable, such as the one analyzed in this study, which requires patients’ memory to recall the date of an event, which sometimes occurred many years before.

In conclusion, they highlight the diagnostic value of the “age” of the “first episode” of syncope as a relevant finding, due to its association with the clinical characteristics and the “final diagnosis”:

Shows a “bimodal” age pattern

In those over 60 years of age, most will have their first “late” episode (≥60 years) and they will have HO and ESC more often compared to those who had “early” syncope. On the contrary, when the first episode occurred “early” (<30 years), the occurrence of prodromes, SVV and complex syncope were more frequent.

Finally, it is worth noting that, despite being evaluated in a syncope unit of a tertiary hospital, a significant proportion of patients (approximately 20%) persisted with the diagnosis of “unexplained syncope” (TTND) and the need for further evaluations or diagnoses. reevaluation.


Roberto Keegan, MD

LAHRS Co-Chair/Representative of the European Heart Rhythm Association (EHRA) Electrophysiology Certification Subcommittee 2020-2022

Former President of the Latin American Heart Rhythm Society (LAHRS) 2017-2018

Director of Electrophysiology – Hospital Privado del Sur and Hospital Español – Bahía Blanca – Argentina


1. Brignole M, Moya A, de Lange FJ, et al. 2018 ESC Guidelines for the diagnosis and management of syncope. Eur Heart J. 2018. http://dx.doi.org/10.1093/eurheartj/ehy037.

2. Colman N, Nahm K, Ganzeboom KS, et al. Epidemiology of reflex syncope. Clin Auton Res. 2004;14 Suppl 1:9-17. http://dx.doi.org/10.1007/s10286-004-1003-3.

3. Duncan GW, Tan MP, Newton JL, et al. Vasovagal syncope in the older person: differences in presentation between older and younger patients. Age Ageing. 2010;39(4):465-70. http://dx.doi.org/10.1093/ageing/afq039.

4. Cooke J, Carew S, Costelloe A, et al. The changing face of orthostatic and neurocardiogenic syncope with age. QJM. 2011;104(8):689-95. http://dx.doi.org/10.1093/qjmed/hcr032.

5. Ceccofiglio A, Mussi C, Rafanelli M, et al. Increasing Prevalence of Orthostatic Hypotension as a Cause of Syncope With Advancing Age and Multimorbidity. J Am Med Dir Assoc. 2019;20(5):586-8. http://dx.doi.org/10.1016/j.jamda.2019.01.149.

6. Parry SW, Kenny RA. Vasovagal syncope masquerading as unexplained falls in an elderly patient. The Canadian journal of cardiology. 2002;18(7):757-8.

7. Tan MP, Parry SW. Vasovagal syncope in the older patient. Journal of the American College of Cardiology. 2008;51(6):599-606. http://dx.doi.org/10.1016/j.jacc.2007.11.025.

8. Yasa E, Ricci F, Magnusson M, et al. Cardiovascular risk after hospitalisation for unexplained syncope and orthostatic hypotension. Heart. 2018;104(6):487-93. http://dx.doi.org/10.1136/heartjnl-2017-311857.

9. Torabi P, Rivasi G, Hamrefors V, et al. Early and late-onset syncope: insight into mechanisms. Eur Heart J. 2022. http://dx.doi.org/10.1093/eurheartj/ehac017.

10. Ganzeboom KS, Colman N, Reitsma JB, et al. Prevalence and triggers of syncope in medical students. Am J Cardiol. 2003;91(8):1006-8, A8. http://dx.doi.org/10.1016/s0002-9149(03)00127-9.

11. Sheldon RS, Sheldon AG, Connolly SJ, et al. Age of first faint in patients with vasovagal syncope. Journal of cardiovascular electrophysiology. 2006;17(1):49-54. http://dx.doi.org/10.1111/j.1540-8167.2005.00267.x.

Call for public comment – 2022 HRS/APHRS/LAHRS Guideline on Cardiac Physiologic Pacing for the Avoidance and Mitigation of Heart Failure

The LAHRS, APHRS and HRS invites interested stakeholders to submit comments on the draft recommendations of the 2022 HRS/APHRS/LAHRS Guideline on Cardiac Physiologic Pacing for the Avoidance and Mitigation of Heart Failure. This open public comment stage provides greater transparency in the clinical practice document development process and the opportunity for key stakeholders to offer feedback before the document’s finalization and publication. All comments will be reviewed, and recommendations edited as appropriate.

The clinical practice guideline is intended to provide comprehensive guidance to electrophysiologists, cardiologists, and other health care providers in the use of pacing in patients with bradycardia-only indications and those in heart failure without bradycardia indications.

Document goals:

  • Introduce the general concepts of cardiac physiologic pacing, which includes conductions system pacing and cardiac resynchronization therapies

  • Review indications for cardiac physiologic pacing to improve outcomes and reduce risk of unnecessary procedures

  • Discuss optimal approaches for pre-procedure, at the time of implant, and follow-up practices

  • Identify opportunities for shared decision making to improve patient outcomes and experiences

  • Provide recommendations for troubleshooting unfavorable responses

If you have questions or experience technical difficulties entering your comments, please contact clinicaldocs@hrsonline.org

Download the document: CPP Guideline_Public Comment_2022.03.18_0


17th edition Arrhythmias Venice 2022

The next October 13-15th, the 17th edition of Venice Arrhythmias 2022 will take place, in Venice, Italy.
LAHRS will participate in a join session called “Topics in modern electrophysiology: A
Latin American perspective for a global health problem”
Drs. M. Figueiredo, J.C Pachón Mateos, E. Saad, M. Scanavacca, Manlio Marquez and D. Hachul.
For more information: https://www.venicearrhythmias.org/va2022-program

Latin American Heart Rhythm Society & The Ohio State University EP Fellowship Program

Overview: The Latin American Heart Rhythm Society (LAHRS) represents the largest and most prestigious association of Electrophysiologists in Latin America The Ohio State University is among the largest universities in the US and a global leader in clinical electrophysiology and electrophysiology research. The Clinical Cardiac Electrophysiology Fellowship at The Ohio State University Wexner Medical Center and Ross Heart Hospital has been accredited since July 1, 1990 with the Electrophysiology section consisting of eight full-time Board-Certified Electrophysiologists and 6 state-of-the-art cardiac electrophysiology (EP) laboratories. The OSU faculty is committed to exceptional clinical care in an investigative atmosphere.  The EP section has a close working relationship with nationally acclaimed programs at The Ohio State University, including Congestive Heart Failure and Genetics, which allow for fellows to train in areas where EP overlaps with other subspecialties. The LAHRS & OSU EP Fellowship Program seeks to build an international relationship to foster the next generation of leaders in the electrophysiology field, while enhancing diversity at OSU and providing opportunities for the most promising young physician-scientists in South America. It is expected that participating fellows will join our program and call The Ohio State University their second home.
Environment: The clinical cardiac electrophysiology outpatient volume at The Ohio State University is a strength of the program with 9,483 patients visiting the Arrhythmia Clinic in 2020. The Device Service interrogated over 32,000 devices (2/3 pacemakers and 1/3 ICDs) in 2020 and had 5,000 in-person device evaluations. Each of the 6 dedicated EP labs is equipped with state-of-the-art recording and advanced mapping systems (ESI & CARTO), cryo-ablation equipment and intracardiac ultrasound. The newest EP lab is a hybrid facility with surgical support and is used mainly for device implantation. There is also a non-invasive EP lab for Tilt Table test, cardioversion and DFT testing. The total number of procedures in the EP labs was 4,336 in 2020 with the number expected to grow. There were 1300 devices implanted including single, dual and Bi-V paces and ICD’s including Implantable loop recorders and hemodynamic monitor recording. In addition, invasive EP testing is done regularly totaling 3000 procedures in 2020 including approximately 1200 ablations.
The Davis Heart and Lung Research Institute (DHLRI) is an interdisciplinary research program encompassing fundamental research, education, and preventive efforts in heart and lung diseases. Faculty in the Institute study integrated aspects of cardiopulmonary function including heart failure and arrhythmia, atrial fibrillation and stroke, cardiac metabolism and diabetes, myocardial injury and repair, vascular biology, cell excitability and contractility, genetic and environmental factors in disease, and development. The physical plant encompasses over 200,000 sq ft of research space supporting over 90 principal investigators in the OSU Wexner Medical Center with shared equipment to support modern molecular biology, cell biology, animal physiology, electrophysiology, optical mapping, cell culture, and virus production.

Applicant requirements: Applicants will be considered if they are LAHRS members, have completed Clinical Cardiac Electrophysiology training (or if they are in the last year of their training) in the country of origin, have proficiency in spoken and written English, with the ability to obtain a visa to enter the USA.

Applicant Selection: A review committee consisting of LAHRS and OSU faculty will review applications and make recommendation for funding to the Program Directors, who will make final decision regarding award.

Duration: One-year fellowship program with an option for a second year.

Starting Date: July 1st 2022 with two weeks of vacation in a year period.

Directors of the Program: Thomas Hund, PhD (Research) and Raul Weiss, MD (Clinical)

Salary: Annual stipend of $50,000.00 US. Transportation, housing and medical insurance are not covered and remain the sole responsibility of the Fellow.

Location: The Ross Heart Hospital and the Dorothy M. Davis Heart and Lung Research Institute (DHLRI) at The Ohio State Wexner Medical Center in Columbus, Ohio, USA. The Ross and DHLRI buildings are adjacent and physically connected by bridges and tunnels.

Structure: This program is a combined clinical electrophysiology and research in electrophysiology. The program time commitment is 30% clinical and 70% research.

A-Didactic. The Fellow will participate in 3 weekly conferences. 1-Tracing rounds, 2-Fellows Conference and 3-Bootcamp (description of each of these conferences are attached)
B-Clinical Service. The Fellow will be observing cases in the Electrophysiology Laboratory, seeing inpatients and outpatient consults with the EP team and spending time in the Device Clinic.

The Fellow will spend at least 3 days a week working on a translation research project under the supervision of the assigned research mentor. Mentorship will be determined by the Directors in consultation with the review committee based on Fellow interest and prior experience, mentor availability and research priorities within DHLRI. An important aspect of this program is the commitment of OSU/DHLRI faculty to advise and mentor the Fellow with at least 1 manuscript in a peer-reviewed journal over the course of the program. Fellows will be expected to attend weekly Research-in-Progress seminars in DHLRI as well as the annual DHLRI Research Day with at least one internal research presentation over the course of their fellowship. In addition, there will be a commitment from OSU, LAHRS and the Fellow to continue collaboration upon the Fellow’s return to their country of origin.

Be a LAHRS member
Complete training in clinical electrophysiology (or in last year of fellowship)
Fluency in spoken and written English


In memoriam, Dr. George Wyse

Dr. George Wyse, in memoriam

It is with mixed feelings that I have the sad task of informing the DOC members of the passing of one of our most esteemed and admired colleagues, who laid the foundations for the Division, Department, and Institute we all are members, Dr. George Wyse.

I met George in 1991 when I was a fellow at UWO. He was always very encouraging, and his inquisitive and witty demeanor always struck me and inspired me as a clinician investigator.

George joined the University of Calgary in 1974 after his undergraduate training initially in Pharmacy in 1964 and Pharmacology (MSc) at UBC. Having been awarded a Medical Research Council Studentship he moved to the University of Manitoba and then following his mentor Dr. Nickerson, to McGill University where he obtained his PhD. in 1969. Once he finished, he was interested in going to Medical School but chose to do a post-doc fellowship at the University of Michigan with Dr. Beck who by the time George’s visa paperwork was available, Dr. Beck had become the Chair of Pharmacology at the University of New Mexico where George and his family went for his post doc training. He joined the faculty there as an Assistant Professor. Due to social unrest related with the Vietnam War he and his family decided to return to Canada. George was able to join the University of Calgary both as Assistant Professor of the Department of Pharmacology and simultaneously going to medical school supported by one of the first HSFC Medical Scientist awards in Canada in 1971 and graduating as an MD in 1974. He then completed 2 years on training in Internal Medicine, at the same time being an Assistant Professor, here at the University of Calgary. He then moved to Portland, Oregon where he trained in Cardiology and was exposed to Clinical Cardiac EP where he became fascinated by this new field and trained with one of the giants in Cardiology and Early EP fathers Dr. Rahimtoola. He returned to Calgary in 1978 and supported by a HSFA Clinical Investigatorship between 1978-84 he founded the clinical cardiac arrhythmia group in Calgary with Brent Mitchell and Hank Duff. This being one of the preeminent EP groups in the country. George rapidly moved up the ranks both academically and administratively becoming a Professor in 1985 and Chief of our Cardiology division between 1986-1993 and Associate Dean Clinical affairs 1993-1999. He became an Emeritus Professor in 2005 and continued his clinical practice until 2016.

George’s research career was initially focused in exploring mechanisms of antiarrhythmic drugs and the prevention of ventricular arrhythmias. He rapidly moved from bench to bedside and became one of the fathers of clinical trials in Canada and internationally. A seminal small RCT published in NEJM in 1987 comparing non-invasive vs invasive strategies for selecting drug therapies for ventricular arrhythmias was the foundation for the famous practice changing Cardiac Arrhythmia Suppression Trial (CAST). The story behind the CAST trial and how he and the EP group in Calgary had suggested the design by the acronyms of CATS vs DOGS trials is both hilarious and inspirational. I recommend that you all watch George’s University of Calgary 2017 Lecture of a Lifetime in youtube to celebrate his passing.   https://www.youtube.com/watch?v=bBJugTvOW9Y

George was also heavily involved with NASPE/HRS and was a member of the Board of Trustees, Similarly his contribution to the Canadian Heart Rhythm Society and Canadian Cardiovascular Society were enormous. 

It is impossible to summarize George’s impact on clinical practice from reversal trials such as CAST and AFFIRM to many other clinical trials that changed and improved the care of arrhythmia and cardiovascular diseases patients globally: AVID, MUSTT, CAMIAT, CIDS, AF-CHF, TOTAL, NAVIGATE-ESUS PATCH, PAPABEAR, VPS I-II, to name just a few. He also played a seminal role in the implementation and knowledge translation of national and international guidelines in many aspects of cardiac arrhythmias. In his later stage of his career, he was a member and Chair of most of the Data Safety Monitoring Boards of the most important and practice changing clinical trials globally.

George was a visionary, innovator a selfless mentor of many here and across the country. We tend to think that we are all replaceable, but George isn’t he was one of a kind and the footprint he leaves on our group will never erase. We celebrate his passing and feel honored to have shared his knowledge, wit, and teachings.

George was an adored father, grandfather, and husband, He and Bonnie partners for a lifetime, 58 years, chose to leave us together on January 6th. They will both be dearly missed.

Our deepest condolences to the family and friends of Dr. George and Bonnie Wyse. https://www.bowriverfuneral.com/index.php?f=obit%2C876

 Carlos A. Morillo, MD

APT MEDICAL offers free registration for LAHRS 2021

APT MEDICAL will take part in LAHRS 2021 and is offering registration free of charge for 100 participants to attend the congress. The event will be completely online and will take place from November 19th to 27th.

Those who wish to apply for the benefit must register at: https://bit.ly/3vI5YKe.

While filling out the registration form, the platform will request information about your preferred payment method. At this point, please request the application for an APT MEDICAL grant.

Renowned experts from several countries will attend LAHRS 2021, including specialists from Brazil, Colombia, Argentina, and Mexico.

Follow LAHRS on Twitter @LAHRSonline1 stay up to date with our latest newsand visit our website at lahrs.org

Follow APT MEDICALon social media: @AptMedDevices

Save The Date – LAHRS 2021

The LAHRS 2021 Congress website is out now! This year, our event will be held completely online and it will take place from November 20th to 27th, 2021! Visit now: http://www.lahrscongress.com/lahrs2021.

In eight days throughout the event, we will offer all the best to our attendees and partners. We are preparing our scientific programme to promote the latest in training and technique.

Submit your abstract!

You can submit your scientific paper to LAHRS 2021 now, from September 1st to October 3rd. Please register at the Congress website to submit your work: http://www.lahrscongress.com/lahrs2021/abstracts/submission.

Please read the rules and instructions to submit your paper and join us!

JICE – Journal of Interventional Cardiac Electrophysiology, LAHRS official journal

The Journal of Interventional Cardiac Electrophysiology is an international publication devoted to fostering research in and development of interventional techniques and therapies for the management of cardiac arrhythmias. It is designed primarily to present original research studies and scholarly scientific reviews of basic and applied science and clinical research in this field.

LAHRS members can read the journal at: https://lahrs.org/jice-lahrs/.

On the home page, click on the cover of the journal to access it with your login name and password. There! Now you can read the latest articles and papers on the most important interventional therapies and trailblazing techniques. The Journal is directed at clinical practitioners and investigators in the field of interventional electrophysiology.

LAHRS to hold exam in Electrophysiology in partnership with EHRA

In April 2021, LAHRS conducted a survey with its members to learn whether they would be interested in taking an Electrophysiology proficiency exam with EHRA. The poll results show that most members would be interested in taking the exam. Therefore, LAHRS and EHRA have established a partnership and the examination will be performed online on November 6th, 2021.

The registration process will start soon! LAHRS members are entitled to special fees. Check it out:

Standard Fee: €750
EHRA or LAHRS Member Fee: €625
LAHRS and EHRA Member Fee: €525

Save the date to take this important certification examination. The main goal with the exam is to guarantee the best treatment of patients suffering from cardiac arrhythmias, by assessing the knowledge, experience, expertise of physicians.

More information on how to register soon. To stay up to date, check this website: https://www.escardio.org/Education/Career-Development/Certification/EHRA-Certification