Mechanical thrombectomy of COVID-19 DVT with congenital heart disease leading to phlegmasia cerulea dolens: a case report.

BACKGROUND: COVID-19 and Fontan physiology have each been associated with an elevated risk of venous thromboembolism (VTE), however little is known about the risks and potential consequences of having both. CASE PRESENTATION: A 51 year old male with tricuspid atresia status post Fontan and extracardiac Glenn shunt, atrial flutter, and sinus sick syndrome presented with phlegmasia cerulea dolens (PCD) of the left lower extremity in spite of supratherapeutic INR in the context of symptomatic COVID-10 pneumonia. He was treated with single session, catheter directed mechanical thrombectomy that was well-tolerated. CONCLUSIONS: This report of acute PCD despite therapeutic anticoagulation with a Vitamin K antagonist, managed with emergent mechanical thrombectomy, calls to attention the importance of altered flow dynamics in COVID positive patients with Fontan circulation that may compound these independent risk factors for developing deep venous thrombosis with the potential for even higher morbidity.

[Diffuse large B-cell lymphoma with mediastinal bulky mass associated with complication of repeated sinus arrest].

A 71-year-old woman presented to a clinic with the chief complaint of facial edema and dyspnea; chest radiography showed mediastinal mass shadow and right pleural effusion. Computed tomography guided biopsy of the mediastinal mass had been performed by her previous doctor, and she was diagnosed with diffuse large B-cell lymphoma. She was referred to our hospital for chemotherapy. Electrocardiography performed before initiating chemotherapy showed sinus arrest for about 4 s, and Holter electrocardiography showed sinus arrest for up to about 7.4 s, which was repeatedly observed 6 times, indicating sick sinus syndrome (SSS). The mediastinal mass completely excluded the superior vena cava, and considering the risk of infection, an extracorporeal pacemaker was not inserted. We believed that the tumor effect was the cause of sinus arrest; hence, chemotherapy initiation was prioritized. R-CHOP therapy preceding vincristine and prednisolone was started, and sinus arrest was not observed after initial treatment. SSS may have been caused by carotid hypersensitivity syndrome that involved the exclusion of carotid artery pressure receptors by the tumor or the direct stimulation of the vagus nerve by microtumor infiltration.

Sinus Node Dysfunction due to Occlusion of the Sinus Node Artery during Percutaneous Coronary Intervention.

BACKGROUND: Sinus node artery occlusion (SNO) is a rare complication of percutaneous coronary intervention (PCI). We analyze both the short- and long-term consequences of SNO. METHODS: We retrospectively reviewed 1379 consecutive PCI's involving RCA and Cx arteries performed in our heart institute from 2016 to 2019. Median follow-up was 44 ± 5 months. RESULTS: Among the 4844 PCIs performed during the study period, 284 involved the RCA and the circumflex's proximal segment. Periprocedural SNO was estimated by angiography observed in 15 patients (5.3%), all originated from RCA. The majority of SNO occurred during urgent and primary PCIs following acute coronary syndrome (ACS). Sinus node dysfunction (SND) appeared in 12 (80%) of patients. Four (26.6%) patients had sinus bradycardia, which resolved spontaneously, and 8 (53.3%) patients had sinus arrest with an escaped nodal rhythm, which mostly responded to medical treatment during the first 24 hours. There was no association between PCI technique and outcome. Three patients (20%) required urgent temporary ventricular pacing. One patient had permanent pacemaker implantation. Pacemaker interrogation during follow-up revealed a recovery of the sinus node function after one month. CONCLUSION: SNO is rare and seen mostly during angioplasty to the proximal segment of the RCA during ACS. The risk of developing sinus node dysfunction following SNO is high. SND usually appears during the first 24 h of PCI. The majority of SND patients responded to medical treatment, and only in rare cases were permanent pacemakers required.

Sinus node disfunction in an adolescent with systemic lupus erythematosus.

Cardiac involvement in systemic lupus erythematosus (SLE) is well documented. The pericardium, myocardium and endocardium, as well as the coronary arteries, the valves and the conduction system can all be affected. While pericarditis is common, arrythmias are less frequently described.We present a 13-year-old male, who had fatigue, anorexia, weight loss, myalgias and arthralgias for four months. On physical examination, we identified bradycardia (heart rate 31-50 bpm), oral and nasal ulcers and polyarthritis. The laboratory results showed hemolytic anemia, hypocomplementemia, antinuclear and anti-dsDNA antibodies, hematuria and non-nephrotic proteinuria. Renal function was normal. Lupus nephritis class II was diagnosed by kidney biopsy. On the transthoracic echocardiogram we identified a minimal pericardial effusion, suggesting pericarditis, and, on the electrocardiogram, we detected sinus arrest with junctional rhythm, denoting sinus node dysfunction. The patient was diagnosed with juvenile SLE with cardiac, renal, musculoskeletal and hematologic involvement. Disease remission and cardiac rhythm control were obtained with steroids and mycophenolate mofetil. Currently, the patient is asymptomatic, with normal sinus rhythm.We described an adolescent with SLE who had sinus node dysfunction upon diagnosis. Other cases have been reported in adults but none in juvenile SLE. All SLE patients should have a thorough cardiac examination to promptly diagnose and treat the innumerous cardiac manifestations of this disease.

Prevalence, Incidence, and Impact on Mortality of Conduction System Disease in Transthyretin Cardiac Amyloidosis.

Transthyretin cardiac amyloidosis (ATTR-CA) is an increasingly recognized infiltrative cardiomyopathy in which conduction system disease is common. The aim of our study was to define the incidence and prevalence of high-grade atrioventricular (AV) block requiring pacemaker implantation in our quaternary referral center. This was a single-center retrospective cohort study of 369 consecutive patients with ATTR-CA who underwent 12-lead electrocardiogram at the time of ATTR-CA diagnosis. During a mean follow-up of 28 months, serial ECGs and the electronic medical record were examined for the development of high-grade AV block and pacemaker implantation. Wild-type ATTR-CA (wtATTR-CA) was diagnosed in 261 patients and 108 had hereditary ATTR-CA (hATTR-CA). A total of 35 (9.5%) had high-grade AV block requiring pacemaker implantation at the time of diagnosis of ATTR-CA. The most common conduction abnormalities evident on the baseline ECG were a wide QRS complex, present in 51% with wtATTR-CA and 48% with hATTR-CA (p = 0.62), followed by first-degree AV block, which was present in 49% with wtATTR-CA and 43% with hATTR-CA (p = 0.31). During follow-up, high-grade AV block developed in 10% of those with hATTR-CA and 12% of patients with wtATTR-CA (p = 0.64). On multivariable models, high-grade AV block was not significantly associated with increased mortality. More advanced ATTR-CA stage and a history of obstructive coronary artery disease were associated with increased mortality on multivariable models. In conclusion, the incidence and prevalence of high-grade AV block is high in patients with ATTR-CA. Patients with ATTR-CA require close monitoring during follow-up for the development of conduction system disease.

Aging-associated sinus arrest and sick sinus syndrome in adult zebrafish.

Because of its powerful genetics, the adult zebrafish has been increasingly used for studying cardiovascular diseases. Considering its heart rate of ~100 beats per minute at ambient temperature, which is very close to human, we assessed the use of this vertebrate animal for modeling heart rhythm disorders such as sinus arrest (SA) and sick sinus syndrome (SSS). We firstly optimized a protocol to measure electrocardiogram in adult zebrafish. We determined the location of the probes, implemented an open-chest microsurgery procedure, measured the effects of temperature, and determined appropriate anesthesia dose and time. We then proposed an PP interval of more than 1.5 seconds as an arbitrary criterion to define an SA episode in an adult fish at ambient temperature, based on comparison between the current definition of an SA episode in humans and our studies of candidate SA episodes in aged wild-type fish and Tg(SCN5A-D1275N) fish (a fish model for inherited SSS). With this criterion, a subpopulation of about 5% wild-type fish can be considered to have SA episodes, and this percentage significantly increases to about 25% in 3-year-old fish. In response to atropine, this subpopulation has both common SSS phenotypic traits that are shared with the Tg(SCN5A-D1275N) model, such as bradycardia; and unique SSS phenotypic traits, such as increased QRS/P ratio and chronotropic incompetence. In summary, this study defined baseline SA and SSS in adult zebrafish and underscored use of the zebrafish as an alternative model to study aging-associated SSS.

Altered heart rate variability in angiotensin II-mediated hypertension is associated with impaired autonomic nervous system signaling and intrinsic sinoatrial node dysfunction.

BACKGROUND: Hypertensive heart disease is associated with sinoatrial node (SAN) dysfunction and reductions in heart rate variability (HRV). Alterations in HRV could occur in association with changes in autonomic nervous system (ANS) activity, changes in SAN function and responsiveness to ANS agonists, or both. These relationships are unclear. OBJECTIVE: The purpose of this study was to investigate the roles of ANS signaling, intrinsic SAN function, and changes in HRV in a mouse model of angiotensin II (AngII)-mediated hypertensive heart disease. METHODS: Mice were treated with saline or AngII (2.5 mg/(kg⋅d)) for 3 weeks. ANS activity was assessed through HRV analysis of electrocardiograms collected in vivo by telemetry as well as direct recordings of vagal nerve activity and renal sympathetic nerve activity from anesthetized mice. The effects of the ANS agonists isoproterenol and carbachol on SAN function and beating interval variability were assessed from electrogram recordings in intact isolated atrial preparations and from spontaneous action potential recordings in isolated SAN myocytes. RESULTS: Time and frequency domain analysis demonstrates that mice infused with AngII had reduced HRV. AngII-infused mice had elevated renal sympathetic nerve activity while resting vagal nerve activity was unchanged. AngII caused an increase in SAN beating interval variability in isolated atrial preparations and isolated SAN myocytes. Furthermore, isolated atrial preparations and SAN myocytes from AngII-infused mice had impaired responses to both isoproterenol and carbachol. CONCLUSION: Reduced HRV in hypertension occurs in association with altered sympathovagal balance as well as intrinsic SAN dysfunction and reduced responsiveness of SAN myocytes to ANS agonists.

Delayed-onset sinus node dysfunction in a child victim of Russell's viper bite.

Cardiac complications following envenomation by Russell's viper venom are uncommon. We describe a 14-year-old girl who developed delayed-onset sinus node dysfunction. She presented with mucosal bleeding, ptosis, and muscle weakness. Her 20-min whole blood clotting time and international normalized ratio were prolonged. The initial electrocardiogram showed sinus tachycardia. Her systemic manifestations responded to antivenom serum. After 24 h, she developed bradycardia and electrocardiography showed sinus node dysfunction with sinus arrest and an atrial escape rhythm. This case shows that arrhythmias can have a delayed onset even after resolution of other systemic manifestations, and even after treatment with antivenom serum.

Glucocorticoid-sensitive Paroxysmal Atrial Fibrillation, Sick Sinus Syndrome, and Mitral Regurgitation in a Patient with Malignant Rheumatoid Vasculitis.

An 80-year-old woman with rheumatoid arthritis presented with chest pain. Clinical examination revealed new-onset paroxysmal atrial fibrillation with symptomatic sinus pauses and worsening mitral regurgitation, which were both resistant to conventional therapies. Based on her skin lesions, an increase in pleural and pericardial effusion, possible myocardial involvement, and a positive finding for immune complex testing, rheumatoid vasculitis was diagnosed. Subsequent glucocorticoid therapy suppressed systemic inflammation, resulting in structural, functional, and electrical reverse remodeling of the left atrium with complete remission of atrial arrhythmias and also an improvement of mitral regurgitation. This case highlights the importance of evaluating the underlying disease activity in a case of de novo paroxysmal atrial fibrillation associated with systemic autoimmune disease.

Marijuana Induced Sick Sinus Syndrome: A Case Report.

BACKGROUND Marijuana is a commonly abused illicit drug in the United States (US). Regular marijuana usage has been linked to many adverse cardiovascular effects. Our case describes the association of abusing marijuana and the development of sick sinus syndrome. CASE REPORT A 27-year-old male carpenter was admitted to the hospital for recurrent syncopal episodes. He reported 2 episodes of syncope every month for the last 5 years. He denied alcohol or nicotine intake but reports using marijuana daily. He also reported cervical injuries due to syncope in the past. Physical examination was unremarkable. Orthostatic vitals were negative. Electrocardiogram (ECG) showed sinus bradycardia. A series of investigations, including a stress test and tilt table testing, were negative. The drug screen was positive for marijuana. A loop recorder was implanted to evaluate the cause of syncope and was positive for a long sinus pause of more than 3 second, indicative of sick sinus syndrome. The patient was successfully treated with a permanent pacemaker with no further events on follow-up after 6 months. CONCLUSIONS The case we report here adds to the literature that several reversible etiologies are shown to be associated with the development of sick sinus syndrome, in which marijuana abuse can be one of them. We strongly suspect that marijuana was the cause of this patient's sick sinus syndrome after ruling out all the possible etiologies. The relation between marijuana use and sick sinus syndrome needs to be further investigated in the future.

Pacemaker treatment after Fontan surgery-A Swedish national study.

OBJECTIVE: Fontan surgery is performed in children with univentricular heart defects. Previous data regarding permanent pacemaker implantation frequency and indications in Fontan patients are limited and conflicting. We examined the prevalence of and risk factors for pacemaker treatment in a consecutive national cohort of patients after Fontan surgery in Sweden. METHODS: We retrospectively reviewed all Swedish patients who underwent Fontan surgery from 1982 to 2017 (n = 599). RESULTS: After a mean follow-up of 12.2 years, 13% (78/599) of the patients with Fontan circulation had received pacemakers. Patients operated with the extracardiac conduit (EC) type of total cavopulmonary connection had a significantly lower prevalence of pacemaker implantation (6%) than patients with lateral tunnel (LT; 17%). Mortality did not differ between patients with (8%) and without pacemaker (5%). The most common pacemaker indication was sinus node dysfunction (SND) (64%). Pacemaker implantation due to SND was less common among patients with EC. Pacemaker implantation was significantly more common in patients with mitral atresia (MA; 44%), double outlet right ventricle (DORV; 24%) and double inlet left ventricle (DILV; 20%). In contrast, patients with pulmonary atresia with intact ventricular septum and hypoplastic left heart syndrome were significantly less likely to receive a pacemaker (3% and 6%, respectively). CONCLUSIONS: Thirteen percent of Fontan patients received a permanent pacemaker, most frequently due to SND. EC was associated with a significantly lower prevalence of pacemaker than LT. Permanent pacemaker was more common in patients with MA, DORV, and DILV.

Sinus bradycardia after intravenous pulse methylprednisolone therapy in patients with systemic lupus erythematosus.

Sinus bradycardia is reported as an adverse effect of high-dose glucocorticoid therapy. We report three cases of systemic lupus erythematosus, wherein intravenous pulse methylprednisolone was administered. The patients' average baseline heart rate was 72 beats/min, which decreased 30% from baseline at 61 h after beginning the therapy. The average minimum heart rate was 38 beats/min, and this rate continued for 169 h on average. No other causes for bradycardia were found, suggesting that the administration of glucocorticoid pulse therapy resulted in decreased heart rate.

Sick Sinus Syndrome Observed in a Patient with Cholinesterase Deficiency.

A 58-year-old woman complained of general fatigue and was diagnosed with sick sinus syndrome (SSS) by ambulatory electrocardiogram, which demonstrated sinus arrest at midnight and paroxysmal atrial fibrillation (AF) at nighttime. Since her plasma cholinesterase (ChE) activity had been persistently zero, she was diagnosed with ChE deficiency. She refused permanent pacemaker implantation, and treatment with positive chronotropic drugs is ongoing. A novel association of ChE deficiency with SSS is theoretically possible rather than coincident, considering that ChE plays a key role in cholinergic influences on the sinus node leading to sinus bradyarrhythmia and on the atria, causing vagally mediated AF.

Sick Sinus Syndrome After the Maze Procedure Performed Concomitantly With Mitral Valve Surgery.

Background To characterize the development of sick sinus syndrome ( SSS ) after the additive maze procedure ( MP ) during mitral valve surgery. Methods and Results Follow-up data (median, 3.6 years) of 750 patients with a prevalence of rheumatic cause of 57.6% were analyzed. SSS occurred in 35 patients with a time-dependent increase: the incidence rates at 1, 2, and 4 years after surgery were 2.9%, 3.7%, and 4.3%, respectively. The additive MP showed higher risks of SSS development (hazard ratio, 7.44; 95% confidence interval, 3.45-16.05; P<0.001) and pacemaker implantation (hazard ratio, 3.61; 95% confidence interval, 1.95-6.67; P<0.001). Patients who developed SSS showed higher 4-year rates of clinical events (death, stroke, and hospital admission) (67.5±8.5% versus 33.0±1.9%; P<0.001). After adjustment for age and preoperative peak systolic pulmonary artery pressure, the lesion extent (biatrial versus left atrial MP ), not the underlying cause (rheumatic versus nonrheumatic), was independently associated with SSS development (hazard ratio, 3.58; 95% confidence interval, 1.08-11.86; P=0.037). The adverse effect of the biatrial MP was confirmed in patients with trivial or mild preoperative tricuspid regurgitation showing higher SSS incidence (4.6±1.4% versus 1.0±0.7%; P=0.023), not in those with moderate-to-severe tricuspid regurgitation (6.8±1.7% versus 3.8±3.8%; P=0.337). Recurrence of atrial fibrillation was not associated with the lesion extent of the MP . Conclusions After the additive MP , the ongoing risk of SSS development should be acknowledged irrespective of the underlying cause. Considering additive risk of biatrial MP with similar atrial fibrillation recurrence rate, minimizing lesion extent is warranted.

Frequency and Significance of High-Degree Atrioventricular Block and Sinoatrial Node Dysfunction in Patients With Non-ST-Elevation Myocardial Infarction.

Characteristics of conduction disorders after ST-elevation myocardial infarction (STEMI) have been well described. In contrast, limited data are available on the incidence, treatment trends, and prognostic impact of conduction disorders after non-ST-elevation myocardial infarction (NSTEMI). Using the National Inpatient Sample database, we compared the characteristics and outcomes of conduction disorders in patients with a primary diagnosis of STEMI versus NSTEMI between 2010 and 2014. Conduction disorders were classified into‬ high-degree AV block (HDAVB), consisting of complete AV block or Mobitz type II second-degree AV block, and sinoatrial node dysfunction (SND). We identified 135,468 STEMI patients and 281,928 NSTEMI patients. In contrast to the STEMI cohort where HDAVB was more common than SND (2.4% vs 0.5%), SND was observed more often in the NSTEMI cohort, presenting in 2,417 patients (0.9%), followed by HDAVB in 1,745 patients (0.6%). In patients who developed HDAVB, NSTEMI patients were more likely to undergo permanent pacemaker implantation than STEMI patients (30.0% vs 11.6%; p < 0.001). The rate of permanent pacemaker implantation for SND was comparable between STEMI and NSTEMI patients (33.9% vs 30.5%; p = 0.10). In the NSTEMI cohort, patients who developed HDAVB had higher in-hospital mortality than those without any major conduction disorders (16.6% vs 3.8%; p < 0.001). In conclusion, SND was more common than HDAVB in the NSTEMI cohort, in contrast to the predominance of HDAVB observed in the STEMI cohort. About one-third of patients who developed HDAVB after NSTEMI underwent pacemaker implantation, suggesting lower rates of spontaneous resolution of HDAVB, when compared with STEMI patients.

Sinus node dysfunction after surgical atrial fibrillation ablation with concomitant mitral valve surgery: Determinants and clinical outcomes.

OBJECTIVE: We sought to investigate determinants and prognosis of sinus node dysfunction (SND) after surgical ablation of atrial fibrillation (AF) with concomitant mitral valve (MV) surgery. A total of 202 patients who underwent surgical AF ablation with concomitant MV surgery were studied. STUDY DESIGN AND SETTING: SND was defined as electrocardiographic manifestations, such as junctional bradycardia, symptomatic sick sinus syndrome, or symptomatic sinus bradycardia, 7 days after surgery. Baseline clinical and echocardiographic characteristics, rhythm outcomes [AF recurrence or permanent pacemaker (PM) implantation] at 6 and 12 months, and clinical outcomes were compared between patients without SND (n = 165) and those with SND (n = 37) after surgery. RESULTS: Patients with SND showed a significantly larger left atrial volume index (LAVI) and a higher right ventricular systolic pressure than those without SND. In addition, there was a higher likelihood for AF recurrence and PM implantation in patients with SND than in those without SND. Although clinical outcomes did not differ between the two groups, patients with SND had a significantly longer length of hospital stay (p<0.001). In a multivariate analysis, preoperative LAVI was a structural risk factor for SND [hazard ratio (HR): 1.126 per 10 mL/m2; 95% confidence interval (CI): 1.0206-1.236; p = 0.001]. An LAVI cut-off value of 105 mL/m2 showed significant predictive power for SND [sensitivity: 62%; specificity: 64%; area under the curve (AUC): 0.678; p = 0.002]. CONCLUSIONS: In conclusion, preoperative LA size was a structural risk factor for SND after surgical AF ablation during MV surgery. SND was associated with an increased risk for AF recurrence and implantation of permanent PM in patients undergoing concomitant surgical ablation of AF with MV surgery.

Conceptos actuales sobre la clasificación clínica y alteraciones electrofisiológicas en la disfunción del nódulo sinusal / Current concepts about the clinical classification and electrophysiological alterations in the sinus node dysfunction

La disfunción del nódulo sinusal (DNS) es generalmente secundaria a la senescencia del nodo sinusal y del miocardio auricular circundante. Los pacientes con este trastorno son a menudo añosos y en general presentan otras comorbilidades. Los pacientes a menudo buscan atención médica con síntomas de aturdimiento, pre-síncope, síncope y, en pacientes con periodos alternantes de bradicardia y taquicardia, palpitaciones u otros síntomas asociados con una frecuencia cardíaca rápida. Debido a que los síntomas pueden ser de naturaleza variable, inespecíficos y frecuentemente transitorios, a veces puede ser difícil establecer esta relación síntoma-alteración electrocardiográfica. Los hallazgos electrocardiográficos típicos son uno o más episodios de bradicardia sinusal extrema (Rubenstein Tipo I), o pausas sinusales, paro y bloqueo de salida sinoatrial (Rubenstein Tipo II), o episodios de bradicardia y/o pausas alternantes con taquiarritmias auriculares (Rubenstein Tipo III). Las investigaciones basadas en el registro de electrogramas locales auriculares anormalmente prolongados y fraccionados durante el ritmo sinusal y su distribución característica en la aurícula derecha de pacientes con DNS han aportado un conocimiento importante sobre las propiedades electrofisiológicas de la aurícula patológica. El electrograma auricular anormal traduce una conducción auricular irregular, caracterizada por una actividad eléctrica local no homogénea, relacionada con una conducción anisotrópica, no uniforme y retardada a través de un miocardio auricular patológico, en el que se pueden originar arritmias por reentrada. La detección de electrogramas auriculares anormales en la DNS identifica a un grupo de pacientes con vulnerabilidad auricular aumentada y con una incidencia significativamente mayor de episodios espontáneos o inducidos de fibrilación auricular(AU)

Sinus node dysfunction (SND) is often secondary to senescence of the sinus node and surrounding atrial myocardium. Patients with this disorder are frequently elderly and generally have other comorbidities. Patients with SND often seek medical attention with symptoms of lightheadedness, presyncope, syncope, and, in patients with alternating periods of bradycardia and tachycardia, palpitations and/or other symptoms associated with a rapid heart rate. Because symptoms may be variable in nature, nonspecific, and frequently transient, it may be challenging at times to establish this symptom-rhythm relationship. Typical electrocardiographic findings are one or more episodes of extreme sinus bradycardia (Rubenstein type I), or sinus pauses, arrest, and sinoatrial exit block (Rubenstein type II), or alternating bradycardia and atrial tachyarrhythmias (Rubenstein type III). Investigations based on the recording of abnormally prolonged and fractionated local atrial electrograms during sinus rhythm and their characteristic distribution in the right atrium of patients with SND have provided important knowledge about the pathological atrium electrophysiological properties. Abnormal atrial electrogram results in an irregular atrial conduction, characterized by a non-homogeneous local electrical activity, related to an anisotropic, non-uniform and delayed conduction through a pathological atrial myocardium, in which reentry arrhythmias may arise. Abnormal atrial electrograms detection in SND identifies a group of patients with increased atrial vulnerability and a significantly higher incidence of spontaneous or induced episodes of atrial fibrillation(AU)