Electrocardiographic Manifestations Research Articles

Новый электрокардиографический феномен при синдроме удлиненного интервала QT: клиническое наблюдение

Long QT syndrome (LQTS) is a disease with a high risk of sudden death in children. Individual prognosis is based on additional, primarily electrocardiological markers. Authors represent a clinical case of a rare variant of electrocardiographic manifestation of LQTS in children that wasn’t described previously. A 6 y/o female patient with LQTS, had no complaints, no syncope or sudden death familial cases. The molecular genetic study revealed a de novo mutation in the SCN5A gene which is typical for the third molecular genetic variant of LQTS (LQT3). Holter monitoring noted “hyperadaptation” of the QT interval (slope QT/RR 0.37 with a norm of up to 0.24). During night sleep, episodes of combined T-wave and QRS complex alternans (AT/AQRS) were detected. This pattern has not been previously described in patients with LQTS. Possible mechanisms and prognostic value for the revealed ECG pattern, issues of treatment of patients with LQT3 are discussed. Conclusion: combined T-wave and QRS complex alternans (AT/AQRS) is a new, previously undescribed ECG phenomenon in patients with LQTS that is highly likely to increase the risk for cardiac events. Thus the “hyperadaptation” of the QT interval may be one of the electrocardiological signs of LQT3.

Trends in electrocardiographic and cardiovascular manifestations of patients hospitalised with COVID-19.

Early in the coronavirus disease 2019 (COVID-19) pandemic, a low incidence of cardiovascular complications was reported in Singapore. Little was known about the trend of cardiovascular complications as the pandemic progressed. In this study, we examined the evolving trends in electrocardiographic and cardiovascular manifestations in patients hospitalised with COVID-19. We examined the first 1781 consecutive hospitalised patients with polymerase chain reaction-confirmed COVID-19. We divided the population based on whether they had abnormal heart rate (HR) or electrocardiography (ECG) or normal HR and ECG, comparing the baseline characteristics and outcomes. Cardiovascular complications were defined as acute myocardial infarction, stroke, pulmonary embolism, myocarditis and mortality. The 253 (14.2%) patients who had abnormal HR/ECG at presentation were more likely to be symptomatic. Sinus tachycardia was commonly observed. Troponin I levels (97.0 ± 482.9 vs. 19.7 ± 68.4 ng/L, P = 0.047) and C-reactive protein levels (20.1 ± 50.7 vs. 13.9 ± 24.1 μmol/L, P = 0.003) were significantly higher among those with abnormal HR/ECGs, with a higher prevalence of myocarditis (2.0% vs. 0.5%, P = 0.019), pulmonary embolism (2.0% vs. 0.3%, P = 0.008) and acute myocardial infarction (1.2% vs. 0.1%, P = 0.023). After adjusting for age and comorbidities, abnormal HR/ECG (adjusted odds ratio 4.41, 95% confidence interval 2.21-8.77; P < 0.001) remained independently associated with adverse cardiovascular complications. Over time, there was a trend towards a higher proportion of hospitalised patients with cardiovascular complications. Cardiovascular complications appear to be increasing in proportion over time among hospitalised patients with COVID-19. A baseline ECG and HR measurement may be helpful for predicting these complications.

A Comprehensive Review on the Electrocardiographic Manifestations of Cardiac Sarcoidosis: Patterns and Prognosis.

Cardiac sarcoidosis (CS) refers to cardiac involvement in sarcoidosis and is usually associated with worse outcomes. This comprehensive review aims to elucidate the electrocardiographic (ECG) signs and features associated with CS, as well as examine modern techniques and their importance in CS evaluation. The exact pathogenesis of CS is still unclear, but it stems from an abnormal immunological response triggered by environmental factors in individuals with genetic predisposition. CS presents with non-cardiac symptoms; however, conduction system abnormalities are common in patients with CS. The most common electrocardiographic (ECG) signs include atrioventricular blocks and ventricular tachyarrhythmia. Distinct patterns, such as fragmented QRS complexes, T-wave alternans, and bundle branch blocks, are critical indicators of myocardial involvement. The application of advanced ECG techniques such as signal-averaged ECG, Holter monitoring, wavelet-transformed ECG, microvolt T-wave alternans, and artificial intelligence-supported analysis holds promising outcomes for opportune detection and monitoring of CS. Timely utilisation of inexpensive and readily available ECG possesses the potential to allow early detection and intervention for CS. The integration of artificial intelligence models into ECG analysis is a promising approach for improving the ECG diagnostic accuracy and further risk stratification of patients with CS.

Electrocardiographic manifestations in female team handball players

Electrocardiographic manifestations in female team handball players

ECG manifestations of occlusion of septal perforator of left anterior descending artery

The fourth universal definition of MI defines requires presence of j point elevation in two contiguous leads except v2–3 where the elevation should be equal to or >2 mm in men (2.5 mm in <40 years) and 1.5 mm in women.(1) We present two cases of patients who presented with electrocardiographic manifestations of occlusion of septal perforator of left anterior descending artery and discuss the salient feature of ECG in such patients. We also present the limitations of STEMI criteria given the dynamic nature of acute coronary occlusion and stress on early recognition of this MI.

Electrocardiographic manifestations in female team handball players: analyzing ECG changes in athletes.

Long-term intense training leads to structural, functional, and electrical remodeling of the heart. How different sports affect the heart has not been fully investigated, particularly for female athletes. The aim of the present study was to investigate the morphology of 12-lead resting electrocardiogram (ECG) in elite female handball players compared to non-athlete female subjects. Potential changes will be explored to see if they could be explained by differences in cardiac dimensions and exercise hours. A cross-sectional study of 33 elite female team handball players compared to 33 sex and age-matched, non-athletic controls (age range 18-26 years) was performed. All participants underwent a resting 12-lead ECG and an echocardiographic examination. ECG variables for left ventricular hypertrophy and durations were evaluated and adjusted for cardiac dimensions and exercise hours using ANCOVA analysis. A linear regression analysis was used to describe relation between echocardiographic and ECG measures and exercise hours. The female handball players had larger cardiac dimensions and significantly lower heart rate and QTc duration (Bazett's formula) as well as increased QRS and QT durations compared to controls. The 12-lead sum of voltage and the 12-lead sum of voltage ∗ QRS were significantly higher among handball players. Changes in ECG variables reflecting the left ventricle could in part be explained by left ventricular size and exercise hours. Correlation with exercise hours were moderately strong in most of the echocardiographic measures reflecting left ventricular (LV), left ventricular mass (LVM), left atrium (LA) and right atrium (RA) size. Poor to fair correlations were seen in the majority of ECG measures. Female team handball players had altered ECGs, longer QRS and QT durations, higher 12-lead sum of voltage and 12-lead sum of voltage ∗ QRS as well as shorter QTc (Bazett's formula) duration compared to non-athletic controls. These findings could only partly be explained by differences in left ventricular size. Despite larger atrial size in the athletes, no differences in P-wave amplitude and duration were found on ECG. This suggest that both structural, and to some degree electrical remodeling, occur in the female team handball players' heart and highlight that a normal ECG does not rule out structural adaptations. The present study adds knowledge to the field of sports cardiology regarding how the heart in female team handball players adapts to this type of sport.

Smartphone ECG Based Successful Diagnosis of WPW Syndrome Under Both Resting and Stress Test Conditions: A Case Report

Background: Wolff-Parkinson-White (WPW) syndrome arises from the presence of an accessory pathway in the heart, disrupting normal electrical conduction between the atria and ventricles. Diagnosis via electrocardiography typically reveals characteristic features such as Delta waves, shortened PR intervals, and RR variabilities. Case Summary: The authors present the case of a 23-year-old male with a history of tobacco and alcohol use, exhibiting electrocardiographic manifestations consistent with WPW syndrome. Employing a Smartphone-based 12-lead ECG and bicycle ergometer, additional testing under resting and stressed conditions revealed a spectrum of abnormalities including T-wave inversions, tachyarrhythmias, conduction blocks, ST depressions, shortened PR intervals, and persistent Delta waves. Despite the absence of symptoms, a stress test achieving 10 METS over 5 minutes demonstrated the potential for ventricular tachycardia. Discussion: Following evaluation by a cardiologist, a watchful waiting approach was recommended, with no pharmacological intervention prescribed. This report underscores the utility of smartphone ECG technology in managing WPW syndrome, offering insights into dynamic cardiac responses during stress and informing clinical decision-making. Regular follow-up ECG assessments at six-month intervals were advised to monitor for emerging symptoms. The importance of prompt consultation with a cardiologist upon symptom onset cannot be overstated, given the inherent risk of life-threatening arrhythmias associated with WPW syndrome.

From Waves to Diagnoses: Decoding Electrocardiogram for Improved Cardiac Care

The electrocardiogram (ECG) is a fundamental tool in cardiology, providing invaluable insights into cardiac physiology and detecting various abnormalities. This review article presents a comprehensive overview of ECG interpretation, focusing on the procedure, application, and methodology. The placement of electrodes, ECG paper speed, and measurements of intervals and blocks are discussed in detail. The article emphasizes the importance of a systematic approach to ECG interpretation, highlighting six main sections: determination of heart rhythm, calculation of heart rate, assessment of intervals and blocks, analysis of atrial depolarization patterns, assessment of ventricular depolarization complexes, and delving into the intricate characteristics of ST segments and exploration of the electrocardiographic T-wave manifestations. Specific criteria for identifying abnormalities in each section are provided, along with their associated etiologies and clinical implications. Furthermore, the limitations of ECG as a diagnostic tool are acknowledged, emphasizing the need for clinical correlation and consideration of additional tests. The abstract encapsulates the breadth and depth of the review, conveying the relevance and the profound significance of ECG interpretation in the realm of clinical practice and scientific inquiry.

Clinical profile, electrocardiographic and echocardiographic manifestation in COVID 19 patients and correlation with disease severity.

Clinical profile, electrocardiographic and echocardiographic manifestation in COVID 19 patients and correlation with disease severity.

The electrocardiographic manifestations of pectus excavatum before and after surgical correction

BackgroundPectus excavatum (PEx) can cause cardiopulmonary limitations due to cardiac compression and displacement. There is limited data on electrocardiogram (ECG) alterations before and after PEx surgical repair, and ECG findings suggesting cardiopulmonary limitations have not been reported. The aim of this study is to explore ECG manifestations of PEx before and after surgery including associations with exercise capacity. MethodsA retrospective review of PEx patients who underwent primary repair was performed. ECGs before and after surgical correction were evaluated and the associations between preoperative ECG abnormalities and cardiopulmonary function were investigated. ResultsIn total, 310 patients were included (mean age 35.1 ± 11.6 years). Preoperative ECG findings included a predominant negative P wave morphology in V1, and this abnormal pattern significantly decreased from 86.9% to 57.4% (p < 0.001) postoperatively. The presence of abnormal P wave amplitude in lead II (>2.5 mm) significantly decreased from 7.1% to 1.6% postoperatively (p < 0.001). Right bundle branch block (RBBB) (9.4% versus 3.9%, p < 0.001), rsr' patterns (40.6% versus 12.9%, p < 0.001), and T wave inversion in leads V1-V3 (62.3% vs 37.7%, p < 0.001) were observed less frequently after surgery. Preoperative presence of RBBB (OR = 4.8; 95%CI 1.1–21.6) and T wave inversion in leads V1–3 (OR = 2.3; 95%CI 1.3–4.2) were associated with abnormal results in cardiopulmonary exercise testings. ConclusionElectrocardiographic abnormalities in PEx are frequent and can revert to normal following surgery. Preoperative RBBB and T wave inversion in leads V1–3 suggested a reduction in exercise capacity, serving as a marker for the need for further cardiovascular evaluation of these patients.

Abstract 11956: Arumenamide-787 Suppresses Arrhythmogenesis Associated With the J Wave Syndrome as Well as Hypothermia

Background: The J-wave syndromes (JWS), comprised of Brugada (BrS) and early repolarization syndromes (ERS), increase the risk of life-threatening ventricular arrhythmias in patients resulting in sudden cardiac death. There are limited therapeutic strategies to treat these life-threatening conditions. Present management is via an implantable cardioverter defibrillator and/or medication, including quinidine. However, these treatments may have serious side-effects. Thus, novel therapies are needed to treat JWS. In this study, we investigate the effects of ARumenamide-787 (AR-787) in suppressing the electrocardiographic and arrhythmic manifestations of JWS and hypothermia. Methods: We studied the effects of AR-787 on sodium current (I Na ) and the delayed-rectifier potassium current (I Kr ) in HEK-293 cells stably expressing the α- and β1-subunits of the cardiac (Na V 1.5) sodium channel or the hERG channel. In addition, we studied its effect on the transient outward potassium current (I to ) and calcium current (I Ca ) from dissociated canine ventricular myocytes, along with action potentials and ECG from coronary-perfused right (RV) and left (LV) ventricular wedge preparations. The I to agonist, NS5806, I Ca blocker, verapamil, and sodium current (I Na ) blocker, ajmaline, to induce the electrocardiographic and arrhythmic manifestations of JWS (prominent J waves/ST segment elevation, phase 2 reentry, and polymorphic VT/VF) in right and left canine ventricular wedge preparations. Results: AR-787 exerted pleiotropic effects on the cardiac ion channels. The predominant effect was an inhibition of I to and enhancement of I Na , with subtle effects to inhibit the I Kr and augment I Ca . AR-787 diminished the electrocardiographic J wave and prevented and/or suppressed all arrhythmic activity in canine RV and LV experimental models of BrS, ERS and hypothermia. We observed no arrhythmogenic effects of AR-787 on I Kr . Conclusions: Our findings point to AR-787 as a promising candidate for the pharmacologic treatment of JWS and hypothermia. AR-787 suppresses the electrocardiographic and arrhythmic manifestations of JWS and hypothermia without significant prolongation of the QT interval, as with the classic BrS drug, quinidine.

Abstract 17335: Novel Functional Genomic Studies in Scn1bb Variant Associated With Brugada Syndrome and the Ameliorative Effect of Acacetin

Background: Brugada syndrome (BrS) is a channelopathy associated with the development of life-threatening ventricular tachycardia and fibrillation (VT/VF). At present, pharmacological approaches to therapy are very limited. Objective: To evaluate the effect of an SCN1Bb variant and the effects of acacetin in experimental models of BrS. Methods: We evaluated the effect of acacetin in: 1) HEK293 cells expressing Kv4.3+ KChIP2 and Nav1.5+ SCN1B using patch clamp techniques (22 O C), 2) canine ventricular epicardial myocytes 3) coronary-perfused canine right (RV) preparations and 4) Langendorff-perfused canine whole-heart models of BrS in which the sodium channel blocker ajmaline or the calcium channel blocker verapamil, together with the transient outward current agonist NS5806 were used to provoke the arrhythmic phenotype. Results: Co-expression of SCN5A -WT+ KCND3-WT with KChIP2 + SCN1Bb -R214Q (variant associated with 3 cases of BrS and 1 case of sudden infant death (SIDS)), resulted in a 210% increase in total charge of the transient outward potassium current (I to ) as well as a 56.5% reduction in sodium channel current (I Na ) when compared to SCN1Bb-WT . In the absence of the mutation, acacetin inhibited I to with an IC 50 of 7.2±1.0 μM (n=3) in HEK cells, similar to the value obtained in native epicardial myocytes (6 μM). In the presence of the SCB1Bb mutant, IC 50 was dramatically reduced to 2.6±1 μM (n=5, p&lt;0.05) Mean ±SEM. In the wedge and whole-heart models of BrS, acacetin dose-dependently reduced the epicardial action potential notch recorded from the RV or RVOT. Acacetin (5-10 μM) totally suppressed the electrocardiographic and arrhythmic manifestation of BrS, regardless of the pharmacologic model used to induce the arrhythmic phenotype. All repolarization defects were reversed, resulting in marked diminution of J waves leading to total suppression of VT/VF. Conclusions: Our findings demonstrate the ability of an SCN1Bb variant to dramatically shift the balance of current in the early phases of the RV epicardial action potential by reducing I Na as well as augmenting I to , thus predisposing to the development of the BrS phenotype. Our observations also hold promise for acacetin as a safe and effective pharmacologic treatment for BrS and some cases of SIDS.

Electrocardiographic semi-spiked helmet sign in critically Ill patients: A case series.

ST-segment elevation on electrocardiogram (ECG) is an alarming sign. Although acute myocardial infarction (AMI) is the most common cause of ST-segment elevation, many non-ischemic conditions may produce pseudo-ST segment elevation. Spiked Helmet (SH) sign is one of the pseudo-ST segment elevations that is associated with critical illness and high risk of death. SH sign was characterized by an upward shift starting before the onset of the QRS complex; however, we found some patients presented with a peculiar characteristic on ECG with an upward convex ST-segment elevation after the QRS wave but without elevation before the QRS wave, therefore called Semi-SH sign. Also, this electrocardiographic feature exists in patients with critical disease and is related to poor prognosis. The purpose of this case series is to describe the electrocardiographic Semi-SH sign and enhance the awareness of such electrocardiographic manifestation for clinicians. This case series explores the possibility of severe infection induced electrocardiographic changes resembling spiked-helmet sign. Sepsis-induced secondary myocardial injury or coronary vasospasm. Gastric decompression, antibiotics, diuretics, advanced life support. The outcome of this case series is the association of the electrocardiographic Semi-SH sign with the prognosis. All 3 patients died several days post manifestation of electrocardiographic Semi-SH sign. Like SH sign, electrocardiographic Semi-SH sign is a life-threatening or deadly ECG sign, and therefore early recognition and aggressive treatment are important.

Brugada Syndrome: A Comprehensive Review of Fundamental and Electrophysiological New Findings.

Brugada syndrome is characterized by pronounced J-ST segment elevation in the right precordial leads on surface electrocardiograms. The etiological underpinnings of these distinctive features have been the subject of extensive debate, encompassing various theories related to repolarization anomalies and conduction irregularities. Genetic investigations have unveiled SCN5A, the gene encoding NaV1.5, a critical sodium channel, as the most frequently implicated causative gene, with mutations typically manifesting as loss of function. Nonetheless, the detection rate of SCN5A mutations remains below 20%, underscoring the intricate genetic landscape of the syndrome. Histological analyses have divulged localized structural irregularities, primarily marked by fibrotic alterations, within the right ventricular outflow tract. Electrophysiological inquiries employing direct epicardial mapping techniques have uncovered localized conduction impediments concomitant with modifications in unipolar morphologies within the J-ST segment. Thus, the theory positing conduction abnormalities emerges as a compelling mechanism accounting for J-ST segment elevation. However, the precise mechanisms governing the onset of life-threatening tachyarrhythmias remain shrouded in uncertainty. Recent clinical case reports have proffered evidence supporting the notion that phase 2 reentry, arising from the marked heterogeneity in action potentials within the epicardial domain, may serve as the instigator of premature ventricular contractions, ultimately culminating in ventricular fibrillation. In light of these developments, it becomes increasingly evident that comprehending the mechanisms underlying the electrocardiographic manifestations and lethal arrhythmias in Brugada syndrome necessitates the consideration of a multifaceted perspective, transcending the binary discourse of repolarization versus depolarization anomalies.

Electrocardiographic manifestations of pulmonary stenosis versus pulmonary hypertension

BackgroundRight ventricular hypertrophy can be caused by conditions such as pulmonary stenosis and pulmonary hypertension. ECG is a readily available and affordable test, the aim of this study was the evaluation of the electrocardiographic aspects of pulmonary stenosis, and pulmonary hypertension. MethodsA list of patients diagnosed with isolated pulmonary stenosis and pulmonary hypertension patients hospitalized and treated between 2019 and 2021 were extracted from the hospital archives. Furthermore, the ECG of the patients was analyzed in terms of the prevalence of the variables in the study using FECG Caliper software. Finally, the data of 93 patients (in both groups) were analyzed. ResultsIn this study, 46 patients were in the severe pulmonary stenosis group, and 49 were in the severe or moderate-to-severe pulmonary hypertension group. The heart rate in the pulmonary hypertension group was significantly higher. R/S > 1 in precordial leads differs between the two groups and higher amplitude R wave in V1(p-value = 0.05). in the pulmonary stenosis group. While in the pulmonary hypertension group, R wave growth occurs later, and this ratio is greater than one after V4. Bundle block in the form of RBBB(p-value <0.001) and maximum QRS duration is more in the pulmonary stenosis group(p-value = 0.001). ConclusionOur findings show the different strains of the right ventricle in two groups. It can be concluded that the effects of severe pulmonary stenosis on the ECG are more on the QRS wave and in the form of a block, while severe pulmonary hypertension affects the ST segment and T wave.

Wellens syndrome Type A. Case report

Wellens syndrome is an electrocardiographic manifestation of critical stenosis of the anterior left descending coronary artery, the persistent reversal of the T-wave in the V2 and V3 shunts. It was decided to report the case of a 48-year-old female patient with the aim of describing her clinical and electrocardiographic characteristics. The patient goes to the Emergency Room of Saturnino Lora Provincial Hospital referring oppressive precordial pain of 15 days of evolution, where an electrocardiogram and coronary angiography are performed, being diagnosed with Wellens Syndrome type A. It was considered to report this case because it is not an immediate recognition syndrome and the findings predict with a high sensitivity and specificity the compromise of the proximal part of the anterior descending artery, requiring an early invasive strategy with the aim of avoiding complications such as acute myocardial infarction and death.

A study of socio clinical, biochemical and electrocardiographic changes of yellow oleander seed poisoning in India

Yellow oleander (Thevetia peruviana), which belongs to the Apocyanaceae family, is a common shrub seen throughout the tropics. All parts of the plant contain high concentrations of cardiac glycosides, which are toxic to cardiac muscle and the autonomic nervous system. The main objective of this study was to socio-clinical, biochemical and electrocardiographic changes of yellow oleander seed poisoning. This prospective observational study was conducted over a period of 6 months (March 2022 to September 2022). Oleander seed poison in most prevalent in the 21–40 years age. More the crushed seeds consumed and the delay to admission to the hospital for treatment poorer was the outcome. The most common GI symptoms of yellow oleander poisoning were vomiting (58 %), abdominal pain (28%), diarrhoea (9%), and palpitations (20%), dizziness (18%).Serum potassium levels that were measured during the admission were directly related to the ECG changes. ECG changes were more observed with patients those who consumed seeds in crushed form and this difference is statistically significant (P = 0.0001). Higher incidence of cardiotoxicity was noted with patients those who consumed poison on empty stomach compare to who consumed after food. The Electrocardiographic manifestations was found even with consumption of one seed, number of seeds consumptions independent of cardiotoxicity.Additonally higher mean Potassium value observed in patients who had cardiotoxicity when compared to patient who had no cardiotoxicity. Death of the patients in yellow oleander seed poisoning was independent of quantity of the seeds they have ingested.

Absent Right Coronary Artery in an Active Young Female

Absent Right Coronary Artery in an Active Young Female

Immune Checkpoint Inhibitor-Associated Myocarditis: From Pathophysiology to Rechallenge of Therapy – a Narrative Review

Even if immunecheckpoint inhibitors have revolutionized the landscape of cancer therapy, their use may be complicated by immune-related adverse events. Among these, myocarditis is the most severe complication. The clinical suspicion often arises after clinical symptoms onset and increase in cardiac biomarkers or electrocardiographic manifestations. Echocardiography and cardiac magnetic resonance imaging are recommended for each patient. However, since they may be misleadingly normal, endomyocardial biopsy remains the gold standard for establishing the diagnosis. Until now, treatment has been based on glucocorticoids even if increasing interest has risen in other immunosuppressive agents. Although myocarditis currently imposes immunotherapy discontinuation, case reports have suggested a safety rechallenge in low-grade myocarditis paving the way for further studies to respond to this unmet clinical need.

Clinical characteristics of Danon disease

Objective: To review the clinical data of 7 patients with Danon disease and analyze their clinical characteristics. Methods: The medical records of 7 patients with Danon disease, who were hospitalized in Peking Union Medical College Hospital of Chinese Academy of Medical Sciences from April 2008 to July 2021, were reviewed and summarized, of which 6 cases were diagnosed as Danon disease by lysosomal-associated membrane protein-2 (LAMP-2) gene mutation detection and 1 case was diagnosed by clinicopathological features. Clinical manifestations, biochemical indexes, electrocardiogram, echocardiography, skeletal muscle and myocardial biopsy and gene detection results were analyzed, and patients received clinical follow-up after discharge. Results: Six patients were male and average age was (15.4±3.5) years and the average follow-up time was (27.7±17.0) months. The main clinical manifestations were myocardial hypertrophy (6/7), decreased myodynamia (2/7) and poor academic performance (3/7). Electrocardiogram features included pre-excitation syndrome (6/7) and left ventricular hypertrophy (7/7). Echocardiography examination evidenced myocardial hypertrophy (6/7), and left ventricular dilatation and systolic dysfunction during the disease course (1/7). The results of skeletal muscle biopsy in 6 patients were consistent with autophagy vacuolar myopathy. Subendocardial myocardial biopsy was performed in 3 patients, and a large amount of glycogen deposition with autophagosome formation was found in cardiomyocytes. LAMP-2 gene was detected in 6 patients, and missense mutations were found in all these patients. During the follow-up period, implantable cardioverter defibrillator implantation was performed in 1 patient because of high atrioventricular block 4 years after diagnosis, and there was no death or hospitalization for cardiovascular events in the other patients. Conclusion: The main clinical manifestations of Danon disease are cardiomyopathy, myopathy and mental retardation. Pre-excitation syndrome is a common electrocardiographic manifestation. Autophagy vacuoles can be seen in skeletal muscle and myocardial pathological biopsies. LAMP-2 gene mutation analysis is helpful in the diagnose of this disease.