Recurrent Unexplained Syncope Research Articles

52-Year-Old Woman With Recurrent Unexplained Syncope

52-Year-Old Woman With Recurrent Unexplained Syncope

Optimization of the clinical workflow and patient pathway in cardiac monitor implantation and follow-up

Abstract Funding Acknowledgements Type of funding sources: Private company. Main funding source(s): Medtronic Background Clinical evidence supports the use of Insertable Cardiac Monitors (ICMs) to determine the aetiology of recurrent unexplained syncope and cryptogenic stroke. ICMs continuously monitor cardiac arrhythmias, enabling appropriate diagnosis and treatment. A remote follow-up system transfers ICM data to hospital staff for analysis. This creates a significant data-burden for the staff. Purpose To assess the impact of efficiency optimization of the diagnostic patient pathway and clinical workflow for patients eligible for an ICM. Methods We collected patient-level data from all patients that received an ICM at a university hospital in 2018 and 2020 to assess the change in the clinical workflow with one year follow-up time. Pathway improvements included moving the procedure out of the catheterization lab (cath lab), switching to a nurse-led pathway as well as outsourcing part of the remote follow-up workflow to an external monitoring centre. Results The number of implanted ICMs doubled from 74 in 2018 to 159 in 2020. In 2018, all implantations were done by a physician while in 2020, 70 % were done by nurses. In 2018 the operation schedule was 60 min for an ICM, compared to 45 minutes in 2020. The waiting time from referral to implantation was significantly shorter in 2020 (mean=36 days) compared to 2018 (mean=49 days), p=0,008. Implantations done in the cath lab decreased significantly (19 % in 2018; 2 % in 2020). Patients receiving an ICM after syncope increased from 71 to 94 patients. Stroke and transient ischemic attack (TIA) as an implantation indication increased substantially from 2018 to 2020 (2 and 62 patients, respectively). In 2018, nurses analysed all remote transmissions. In 2020 the first line review and triaging of remote transmissions was outsourced to an external monitoring and triaging centre. This external service escalated only 11 % of the transmissions (204 out of 1817) to the clinic for revision. Under the assumption that a nurse uses 11 minutes per transmission as seen in previous studies, this saved 296 hours of nursing time in 2020. The nurse-led implantation in 2020 saved 48 hours of physicians’ time compared to what would have been used by the process in 2018. The shorter procedure scheduling freed up additional 40 hours of nursing time in 2020. Also, time in the cath lab was freed up for other procedures (27 hours per year). The complication rate did not change significantly (2,7 % in 2018 and 3,1 % in 2020, P=0,85). The 1-year diagnostic yield for syncope remained high in 2018 and 2020 with no statistically significant difference (26.8 % vs 20.2 % P=0.32). The diagnostic yield for stroke patients implanted in 2020 was 24.6 %. Conclusions Nurse-led care pathways and the use of an external monitoring and triaging service significantly improved the patient pathways for patients indicated for an ICM. This freed up a significant amount of staff time and resources without compromising the quality of the treatment.

Management of Patients With Unexplained Syncope and Bundle Branch Block: Predictive Factors of Recurrent Syncope.

Syncope in patients with bundle branch block (BBB) is often due to advanced atrioventricular (AV) block. The objective of the present "real-world" study was to evaluate the optimal management in patients with unexplained syncope and BBB and to identify factors that predict the recurrence of syncope. This is a single-center observational prospective registry of 131 consecutive patients undergoing invasive electrophysiology study (EPS) for recurrent unexplained presyncope or syncope attacks and BBB. When the EPS-derived diagnosis was reached, a decision to proceed with a permanent pacemaker was offered to the patient. An implantable loop recorder was inserted in the rest of the population. A total of 131 consecutive patients with unexplained syncope and BBB (67.2% male; age 63.7 ± 16.5 years) underwent EPS during the study period. The distribution of conduction disturbance patterns was as follows: isolated left bundle branch block (LBBB): 23.7%; LBBB with first AV block: 8.4%; isolated right bundle branch block (RBBB): 10.7%; RBBB with first AV block: 8.4%; isolated left anterior/posterior fascicular block: 13%; left anterior/posterior fascicular block with first AV block: 5.3%; isolated bifascicular block: 16.8%; and bifascicular block with first AV block: 13.7%. In the multivariate analysis, the only predictors of recurrent syncope were bifascicular block (hazard ratio (HR): 4.16, 95% confidence interval (CI): 1.29, 13.41, P: 0.017) and HV interval ≥ 60 msec (HR: 3.58, 95% CI: 1.12, 11.46, P: 0.032). An EPS-based strategy identifies a subset of patients who will benefit from permanent pacing. HV interval ≥ 60 msec and the presence of a bifascicular block were strongly related to syncope recurrence.

Riesgo arrítmico en episodios únicos o recurrentes de síncope inexplicado con bloqueo completo de rama

Introduction and objectivesPatients with a single syncopal episode (SSE) and complete bundle branch block (cBBB) are frequently managed more conservatively than patients with recurrent episodes (RSE). The objective of this study was to analyze if there are differences between patients with single or recurrent unexplained syncope and cBBB in arrhythmic risk, the diagnostic yield of tests, and clinical outcomes. MethodsCohort study of consecutive patients with unexplained syncope and cBBB with a median follow-up time of 3 years. The patients were evaluated via a stepwise workup protocol based on electrophysiological study (EPS) and long-term follow-up with an implantable cardiac monitor. ResultsOf the 503 patients included in the study, 238 (47.3%) had had only 1 syncopal episode. The risk of an arrhythmic syncope was similar in both groups (58.8% in SSE vs 57.0% in RSE; P=.68), also after adjustment for possible confounding variables (HR, 1.06; 95%CI, 0.81-1.38; P=.674). No significant differences between the groups were found in the EPS results and implantable cardiac monitor diagnostic yield. A total of 141 (59.2%) patients with SSE and 154 (58.1%) patients with RSE required cardiac device implantation (P=.797). After appropriate treatment, 35 (7%) patients had recurrence of syncope. The recurrence rate and mortality were also similar in both groups. ConclusionsPatients with cBBB and unexplained syncope are at high risk of an arrhythmic etiology, even after the first syncopal episode. Patients with SSE and RSE have a similar arrhythmic risk and similar outcomes, and therefore there is no clinical justification for not managing them in the same manner.Full English text available from:www.revespcardiol.org/en

Arrhythmic risk in single or recurrent episodes of unexplained syncope with complete bundle branch block

Introduction and objectivesPatients with a single syncopal episode (SSE) and complete bundle branch block (cBBB) are frequently managed more conservatively than patients with recurrent episodes (RSE). The objective of this study was to analyze if there are differences between patients with single or recurrent unexplained syncope and cBBB in arrhythmic risk, the diagnostic yield of tests, and clinical outcomes. MethodsCohort study of consecutive patients with unexplained syncope and cBBB with a median follow-up time of 3 years. The patients were evaluated via a stepwise workup protocol based on electrophysiological study (EPS) and long-term follow-up with an implantable cardiac monitor. ResultsOf the 503 patients included in the study, 238 (47.3%) had had only 1 syncopal episode. The risk of an arrhythmic syncope was similar in both groups (58.8% in SSE vs 57.0% in RSE; P=.68), also after adjustment for possible confounding variables (HR, 1.06; 95%CI, 0.81-1.38; P=.674). No significant differences between the groups were found in the EPS results and implantable cardiac monitor diagnostic yield. A total of 141 (59.2%) patients with SSE and 154 (58.1%) patients with RSE required cardiac device implantation (P=.797). After appropriate treatment, 35 (7%) patients had recurrence of syncope. The recurrence rate and mortality were also similar in both groups. ConclusionsPatients with cBBB and unexplained syncope are at high risk of an arrhythmic etiology, even after the first syncopal episode. Patients with SSE and RSE have a similar arrhythmic risk and similar outcomes, and therefore there is no clinical justification for not managing them in the same manner.

Permanent pacemaker implantation in unexplained syncope patients with electrophysiology study-proven atrioventricular node disease

ObjectiveSyncope, whose cause is unknown after an initial assessment, has an uncertain prognosis. It is critical to identify patients at the highest risk who may require a pacemaker and to identify the cause of recurrent syncope to prescribe proper therapy. The aim of this study was to evaluate the effect of permanent pacing on the incidence of syncope in patients with unexplained syncope and electrophysiology study (EPS)-proven atrioventricular (AV) node disease. MethodsThis was an observational study based on a prospective registry of 236 consecutive patients (60.20 ± 18.66 years, 63.1% male, 60.04 ± 9.50 bpm) presenting with recurrent unexplained syncope attacks admitted to our hospital for invasive EPS. The decision to implant a permanent pacemaker was made in all cases by the attending physicians according to the results of the EPS. A total of 135 patients received the antibradycardia pacemaker (ABP), while 101 patients were declined. ResultsThe mean of reported syncope episodes was 1.97 ± 1.10 (or presyncope 2.17 ± 1.50) before they were referred for a combined EP-guided diagnostic and therapeutic approach. Over a mean follow-up of approximately 4 years (49.19 ± 29.58 months), the primary outcome event (syncope) occurred in 31 of 236 patients (13.1%), and 6 of 135 (4.4%) patients in the ABP group as compared to 25 of 101 (24.8%) in the no pacemaker group (p < 0.001). ConclusionAmong patients with a history of unexplained syncope, a set of positivity criteria for the presence of EPS-defined AV node disease identifies a subset of patients who will benefit from permanent pacing.

Unmasking of infra-Hisian conduction abnormality by intravenous isoproterenol during electrophysiology study for syncope.

Recurrent unexplained syncope in the background of bundle branch block (BBB) often requires a pacemaker. But the decision-making for pacemaker is difficult in case of single episode of syncope with intermittent bundle branch block. We encountered one such case with intermittent LBBB, where the results of invasive EP study were even normal, until intravenous isoproterenol unmasked the infra-Hisian disease during decremental atrial pacing.

Télésurveillance des Moniteurs cardiaques implantables : Vers une prise en charge ? Évaluation de l'acte par la Haute autorité de santé

Implantable cardiac monitors are recommended and reimbursed in two specific cases: the etiological diagnosis of unexplained recurrent syncope and the etiological diagnosis of a cryptogenic ischemic stroke.According to the French National Authority for Health (HAS), remote monitoring "leads to early diagnosis and therapeutic care". However, remote tracking of these devices for diagnostic purposes is not included in the ETAPES program, which will end soon.This article presents a summary of the evaluation by HAS of the remote monitoring of implantable cardiac monitors. It also addresses the question of its reimbursement, as for therapeutic implantable devices.

Young patient with recurrent unexplained syncope

Ayoung woman with recurrent syncope, which remained unexplained despite multiple cardiologic and neurologic investigations, presented for invasive cardiologic work-up including the implantation of aloop recorder. The diagnosis could be established merely by taking the patient's medical history; further investigations were limited to tilt table testing just to confirm the diagnosis.

Cardiac Magnetic Resonance as a diagnostic tool in arrhythmias

Abstract Funding Acknowledgements Type of funding sources: None. Introduction Etiology of cardiac arrhythmias is often difficult to determine.As the gold standard to anatomical and functional cardiac evaluation,Cardiac Magnetic Resonance(CMR)can be a fundamental technique for accurate assessment of myocardial arrhythmic substrates or for arrhythmias management. Purpose The aim of this study is to determine diagnostic and arrhythmic risk stratification impact of CMR performed in patients with suspected or confirmed arrhythmias. Methods We performed a six-years prospective study of patients with suspected or confirmed arrhythmias which evaluation with other techniques did not provide a definitive diagnosis.These patients underwent CMR for diagnostic and risk stratification assessment.We applied a protocol to evaluate both ventricles’ morphology and functional and late gadolinium enhancement (LGE) presence. Results A total of 93 patients were included,of which 66% were male, with a mean age of 45 ± 17 years old. The indications for patients with suspected or confirmed arrhythmias performing CMR evaluation were the following: 33% (n = 31) of the patients had very frequent premature ventricular complexes, 23% (n = 21) had sustained ventricular tachycardia (VT), 5%(n = 5) non-sustained VT, 17%(n = 16) suspected structural heart disease with high arrhythmic potential,10%(n = 9) unexplained recurrent syncope,9 %(n = 8) supraventricular tachycardia and 3% (n = 3) aborted sudden cardiac death. Depressed ejection fraction (EF)(&amp;lt;50%) was present in 10% (n = 9) for LV(mean EF 38 ± 9%) and 15%(n = 14) for RV (mean EF 42 ± 7%). Dilation of LV was found in 25% of patients (n = 23, mean LV volume: 115 ± 7ml/m²), with RV dilation being present in only 1 patient, who had right ventricle arrhythmogenic dysplasia (RVAD) (RV volume: 152ml/m²). In total, 16%had interventricular septum hypertrophy (mean 15 ± 4mm/m2).We found slight anterior leaflet prolapse of mitral valve in 10% (n = 9) of the cases and mild mitral regurgitation in 15% (n = 14). Left atrium dilation was observed in 17% (n = 16) of patients (mean area of 18 ± 2cm2/m2), as right atrium was dilated in only two. In 20% of the patients, CMR contributed to establish a previously unknown diagnosis: 6% (n = 5) have hypertrophic cardiomyopathy,4%(n = 4)a myocarditis sequelae and 2%(n = 2)had RVAD. LV non-compaction,a silent myocardial infarction scar and non-ischemic dilated cardiomyopathy were diagnosed in 3%of the cases each. In 15%(n = 14)we found nonspecific variations, which deserve follow-up. On the remaining patients, CMR was considered normal. Conclusion As a high reproducible, accurate and versatile technique, CMR allowed an increase on diagnosis in 20% of the patients with suspected or confirmed arrhythmias. Consequently, it contributed to the risk stratification of our study population with suspected high arrhythmic potential when the first-line complementary exams were inconclusive.

Permanent pacemaker implantation in unexplained syncope patients with electrophysiology study-proven atrioventricular node disease

Abstract Funding Acknowledgements Type of funding sources: None. Background/Introduction: Syncope, whose cause is unknown after an initial assessment, has an uncertain prognosis. It is critical to identify patients at highest risk who may require a pacemaker and to identify the cause of recurrent syncope to prescribe proper therapy Purpose Aim of this study was to evaluate the effect of permanent pacing on the incidence of syncope in patients with unexplained syncope and electrophysiology study-proven atrioventricular node disease. Methods This was an observational study based on a prospective registry of 236 consecutive patients (60.20 ± 18.66 years, 63.1% male, 60.04 ± 9.50 bpm) presenting with recurrent unexplained syncope attacks admitted to our hospital for invasive electrophysiology study (EPS). Τhe implantation of a permanent antibradycardia pacemaker (ABP) was offered to all patients according to the results of the EPS. 135 patients received the ABP, while 101 denied. Results The mean of reported syncope episodes was 1.97 ± 1.10 (or presyncope 2.17 ± 1.50) before they were referred for a combined EP guided diagnostic and therapeutic approach. Over a mean follow-up of approximately 4 years (49.19 ± 29.58 months), the primary outcome event (syncope) occurred in 31 of 236 patients (13.1%), 6 of 135 (4.4%) in the ABP group as compared to 25 of 101 (24.8%) in the no pacemaker group (p &amp;lt; 0.001). Conclusion Among patients with a history of unexplained syncope, a set of positivity criteria for the presence of EPS defined atrioventricular node disease, identifies a subset of patients who will benefit from permanent pacing.

Syncope associated with supraventricular tachycardia: Diagnostic role of implantable loop recorders.

Syncope represents a relatively uncommon symptom of supraventricular tachycardia (SVT). It is likely that an impaired autonomic vasomotor response to the hemodynamic stress of tachycardia is the determinant of hemodynamic changes leading to cerebral hypoperfusion and syncope. In this regard, tilt‐table test may detect abnormalities in the autonomic nervous function and predict the occurrence of syncope during SVT. Electrophysiology studies may reproduce the SVT, distinguish it from other life‐threatening ventricular tachyarrhythmias, and exclude other causes of syncope. Not infrequently mixed syncope mechanisms are revealed during the above diagnostic workup raising doubts about the operating mechanism in the clinical setting. In such cases of uncertainty, an implantable loop recorder, providing long‐term cardiac monitoring, may play a pivotal role in the establishment of the diagnosis, confirming the association of an arrhythmic event with the symptom. Herein, we present four such cases with recurrent unexplained syncope finally attributed to paroxysmal SVT guiding them to a potentially radical treatment through radiofrequency catheter ablation.

Implantable loop recorder in unexplained palpitations or syncope: A randomised study among young patients with structurally normal heart

BackgroundThe utility of an implantable loop recorder (ILR) in the evaluation of unexplained syncope or palpitations in young patients in the absence of structural heart disease or ventricular dysfunction is limited. To compare the diagnostic yield of ILR with conventional extended Holter evaluation in the detection of arrhythmias among young patients with a structurally normal heart presenting with unexplained palpitations or syncope. MethodsOpen-label randomised control trial was conducted in a tertiary cardiac care centre among young patients with recurrent unexplained palpitations (≥3 episodes/year) or syncope (≥2 episodes) with normal electrocardiogram and echocardiography, after excluding non-cardiac causes. Patients were block randomised to either ILR implantation or conventional extended Holter monitoring. ResultsFourteen patients in the ILR group and 16 patients in the conventional group completed the study. The mean age of the patients was 31.9 ± 5.5 and 31.2 ± 5.4 years. Males constituted 78.5% and 75% in the two groups, respectively. Diagnosis was established in 10 (71.5%) patients in the ILR group as compared to only 3 (18.7%) in the conventional group (p = 0.01), with an RR of 0.26 (95% CI 0.089–0.76, p = 0.01). The arrhythmias diagnosed with ILR were narrow complex tachycardia (30%), atrial fibrillation (20%), VPCs (20%), severe bradycardia with asystole due to sinus arrest (10%), VPCs with bigeminy (10%), and ventricular tachycardia (10%). ConclusionIn young patients with unexplained syncope or palpitations, ILR has a higher diagnostic yield in the accurate detection of arrhythmia compared with conventional Holter strategy, resulting in better management.

Do implantable loop recorders impact the survival of patients with recurrent unexplained syncope?

Aim: This study compares the outcomes of patients who receive an implantable loop recorder (ILR) for unexplained syncope to a control group without the diagnostic device in German claims data. Methodsand materials: Patients with ILR were matched to a control group based on prior syncope events, age, gender and Charlson Comorbidity index (CCI). Survival, syncope hospitalizations, treatment and costs were compared. Results/conclusion: Four hundred and twelveILR patients were matched with controls, mean age was 68, mean CCI was2.7, 42% females. ILR patients lived on average 1.2years longer than patients in the control group. Twenty-five percent of ILR patients received a therapeutic device compared with 5% in the control group. ILRs might help to diagnose and treat patients with positive impact on survival.

Delayed identification of high-degree atrioventricular block with prolonged asystole revealed after the removal of an implantable loop recorder owing to battery depletion.

There is a need for prolonged monitoring and close follow-up in cases of recurrent unexplained syncope and no diagnosis at the time of ILR explanation. Also, a second ILR should be implanted in cases with no clear diagnosis of syncope that probably has a cardiac origin.

Permanent pacemaker implantation in unexplained syncope patients with borderline sinus bradycardia and electrophysiology study-proven sinus node disease.

BackgroundSignificant sinus bradycardia (SB) in the context of sinus node dysfunction (SND) has been associated with neurological symptoms. The objective was to evaluate the effect of permanent pacing on the incidence of syncope in patients with rather mild degrees of SB, unexplained syncope, and “positive” invasive electrophysiologic testing.MethodsThis was an observational study based on a prospective registry of 122 consecutive mild SB patients (61.90 ± 18.28 years, 61.5% male, 57.88 ± 7.73 bpm) presenting with recurrent unexplained pre and syncope attacks admitted to our hospital for invasive electrophysiology study (EPS). Τhe implantation of a permanent antibradycardia pacemaker (ABP) was offered to all patients according to the results of the EPS. Eighty patients received the ABP, while 42 denied.ResultsThe mean of reported syncope episodes was 2.23 ± 1.29 (or presyncope 2.36 ± 1.20) in the last 12 months before they were referred for a combined EP guided diagnostic and therapeutic approach. Over a mean follow‐up of approximately 4 years (50.39 ± 32.40 months), the primary outcome event (syncope) occurred in 18 of 122 patients (14.8%), 6 of 80 (7.5%) in the ABP group as compared to 12 of 42 (28.6%) in the no pacemaker group (P = .002).ConclusionsAmong patients with mild degree of SB and a history of unexplained syncope, a set of positivity criteria for the presence of EPS defined SND after differentiating reflex syncope, identifies a subset of patients who will benefit from permanent pacing.

Patients with recurrent syncope and implantable loop recorder exhibit better survival than the control group without implantable loop recorder

Abstract Introduction In 30% of patients with syncope, the underlying cause remains unexplained after clinical investigations. Unexplained syncope tends to recur, significantly impacting patients' quality of life of patients and mortality. Thus, there is a need for timely and more accurate diagnosis to initiate treatment. Dedicated care pathways are recommended by ESC guidelines. Purpose Patients with recurrent syncope were followed over time and patient outcomes with ILR were compared to patients with the same syncope burden, age, gender and mortality risk score who did not receive an ILR. Method A representative database of 4.9 million patients insured by German company statuary health insurances (BKK) was analysed over a time period of 10 years, 2007–17. Patients with recurrent syncope (two times ICD-10 GM diagnosis codes R55), age between 45–84 and no diagnosis code for the syncope were included in the analysis and followed for at least 2 years. Patients with ILR were matched to patients without ILR based on age, gender and Charlson Comorbidity index (CCI) using mahalanobis distances. The index event was the device implant in the ILR group and the second syncope event in the control group. Life expectancy, syncope hospitalisations, fall related injuries, health care costs, diagnoses and treatment rates were compared between the groups. Results A total of 412 patients with ILR for recurrent unexplained syncope were matched to the control group. Overall mean age was 68, mean was CCI 2.7, 42% were females. The risk of death was 2.35 times higher in the control group during follow up as shown in Figure 1 (p-value logrank test &amp;lt;0.0001). Cardiovascular related diagnosis and treatment rates were higher in the ILR group with 69% of patients having a cardiology diagnosis compared to 41% in the control group. Over a quarter (27%) of ILR patients received an implantable cardiac device compared to 5% in the control group. Ablation rates were 7% in the ILR group compared to 0% in the control group. Median health care costs were € 3,847 higher in the ILR group including the costs of the ILR implant, follow up and higher rates of cardiac treatments. These extra costs appear moderate given the substantially higher mortality risk in the control group. Conclusion This study of patients with recurrent unexplained syncope shows a remarkable difference in life expectancy in patients with ILR compared to a matched control group. Two large claim data analysis have recently shown higher rates of cardiovascular death as well as all-cause mortality in patients with unexplained syncope. A more vigilant cardiac workup might be needed to identify a possible underlying cardiac condition. Higher rates of cardiac device therapy in the ILR group were likely to play an important role for their better life expectancy. Cardiac therapies such as pacemakers, defibrillators and ablation have also been shown to significantly improve patients' quality of life. Life Expectancy Comparison Funding Acknowledgement Type of funding source: Private company. Main funding source(s): The data analysis was funded by Medtronic

An unexplained recurrent syncope.

An unexplained recurrent syncope.

Pacing in vasovagal syncope: Physiology, pacemaker sensors, and recent clinical trials—Precise patient selection and measurable benefit

The role of pacing in vasovagal syncope (VVS) is considered from a physiological basis. Most VVS patients lose consciousness due to hypotension before severe bradycardia/asystole occurs. Patients who benefit from dual-chamber pacing typically are older with highly symptomatic, late-onset, frequent and severe syncope with short/no prodrome and documented severe cardioinhibition. Tilt testing is of value in patients with recurrent unexplained syncope to identify important hypotensive susceptibility stemming from reduced venous return and stroke volume (SV). A negative tilt test in vasovagal patients with spontaneous asystole documented by an implantable/insertable loop recorder is associated with lower syncope recurrence rates after pacemaker implantation. Pacing may be more effective if triggered by sensor detection of a parameter changing earlier in the reflex than bradycardia when SV may still be relatively preserved. In this regard, detection of right ventricular impedance offers promise. Conservatism is recommended, limiting pacing in VVS to a small subset of symptomatic older patients with clearly documented cardioinhibition and paying particular attention to the timing of loss of consciousness in relation to asystole/bradycardia. Understanding VVS physiology permits application of well-timed, appropriate pacing that yields benefit for highly symptomatic patients.

P603Cardiac Magnetic Resonance evaluation and risk stratification of patients with unexplained or suspected arrhythmias

Abstract Introduction The etiological diagnosis of cardiac arrhythmias is often difficult. Cardiac Magnetic Resonance (CMR) is the gold standard exam for anatomical and functional cardiac evaluation and it may be indicated in patients with ventricular arrhythmias when echocardiography does not provide an accurate assessment of left and right ventricles (LV, RV). Purpose The aim of this study was to determine the impact of CMR in the diagnosis and stratification of arrhythmic risk in patients with confirmed or suspected arrhythmias, as well as to describe the changes observed. Methods We performed a prospective registry over a 5-year period of all the patients with arrhythmias who underwent CMR for diagnostic and risk stratification purposes. We followed a protocol to evaluate both anatomically and functionally the ventricles and to look for the presence of late gadolinium enhancement (LGE). Results A total of 78 patients were included, of which 65% were male and a mean age of 46±17 years-old was observed. The indications for CMR evaluation of patients with confirmed or suspected arrhythmias were as follows: 33% (n=26) of the patients had very frequent premature ventricular complexes (PVC), 23% (n=18) had sustained ventricular tachycardia (VT), 17% (n=13) suspected structural heart disease with high arrhythmic potential, 12% (n=9) unexplained recurrent syncope, 6% (n=5) supraventricular tachycardia, 5% (n=4) non-sustained VT and 4% (n=3) aborted sudden cardiac death. Depressed ventricular ejection fraction (&lt;50%) was present in 9% (n=7) for the LV and in 14% (n=11)for the RV. Dilation of the LV was found in 24% of the patients (n=19, mean LV volume: 115±4ml/m2) and RV dilation was present in only 1 patient who had right ventricle arrhythmogenic dysplasia (RVAD) (RV volume: 152ml/m2). Cardiac synchronization artifacts due to the presence of very frequent PVC compromised the calculation of v volumes in only 4% (n=3) of the patients. In total, 6% (n=5) had interventricular septum hypertrophy (mean 15±6g/m2), 10% (n=8) had a slight prolapse of the anterior leaflet of the mitral valve and 19% (n=15) had a dilated left auricle. LGE was present in 13% (n=10) and slight pericardium effusion was detected in 12% (n=9). CMR was considered normal in 65% (n=51), in 15% (n=12) we found nonspecific changes deserving follow-up and in 20% (n=15) it was possible to establish a diagnosis which was previously unknown: 5% (n=4) had hypertrophic cardiomyopathy, 4% (n=3) LV non-compaction, 4% (n=3) a myocarditis sequelae, 3% (n=2) RVAD, 3% (n=2) a myocardial infarction scar and 1 had non-ischemic dilated cardiomyopathy. Conclusions CMR is a technique with high spatial resolution, feasible and safe, which allowed an increase in diagnosis in 20% of the patients, thus contributing to the risk stratification of our study population with suspected high arrhythmic potential when the first-line complementary exams were inconclusive.