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Berhane Worku

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Stress KillsBerhane Worku MD1, Shudhanshu Alishetti2, Kumudha Ramasubbu21. New York Presbyterian Brooklyn Methodist Hospital/Weill Cornell Medical Center Department of Cardiothoracic Surgery, Brooklyn, NY 112152. New York Presbyterian Brooklyn Methodist Hospital Division of Cardiology, Brooklyn NY 11215Corresponding AuthorBerhane Worku MDDepartment of Cardiothoracic SurgeryNew York Presbyterian Brooklyn Methodist Hospital506 6th StreetBrooklyn, NY 11215The medical, economic, and social consequences of the COVID-19 pandemic have been profound. Severe respiratory failure as well as inflammatory and thrombotic complications have resulted in hundreds of thousands of deaths. Political controversy continues regarding optimal strategies for large scale control of the pandemic. Social distancing policies have led to reduced transmission rates but the economic effects have been devastating. Optimal treatment strategies continue to evolve, and vaccine solutions are on the horizon. In addition to these more obvious issues, other severe consequences of the pandemic are slowly being recognized.In the current report, Kir et. al. describe two postmenopausal women presenting with signs and symptoms of acute coronary syndrome in the setting of severe psychological stress related to social isolation during the COVID-19 pandemic (1). Both were COVID negative and both had unremarkable coronary angiograms. Both were diagnosed with takotsubo cardiomyopathy based on the characteristic findings of angina, mild troponin elevation, electrocardiographic changes, and apical akinesis on echocardiogram. Both admitted to severe anxiety and stress in the days prior to the onset of symptoms. Both improved with conservative management including beta-blockers and anxiolytics with resolution of apical akinesis on follow up echocardiogram.Takotsubo or stress cardiomyopathy is a now well recognized entity typically presenting as angina or dyspnea in the setting of a severe emotional or physical stressor. Postmenopausal women are more frequently affected and a history of psychiatric disorders is frequently noted. Electrocardiographic abnormalities and mild troponin elevations are common. Diagnosis is based on the InterTAK diagnostic score. Echocardiography classically demonstrates apical ballooning with basal hyperkinesis, but other wall motion abnormalities are described usually extending beyond a traditional coronary artery distribution. Coronary angiography is frequently performed to rule out acute coronary syndrome but is unremarkable. The syndrome is typically self-limited, requiring conservative supportive management, but in severe cases can lead to heart failure and shock requiring high-dose pharmacologic support, mechanical circulatory support, and in ~5% of cases can be fatal (2).Emotional and physical stress are risk factors for a variety of conditions including cardiovascular disease. Furthermore, psychiatric disorders such as depression and anxiety are associated with poorer outcomes in the setting of cardiovascular disease. Proposed mechanisms for this include behavioral factors such as noncompliance with medications and lifestyle modifications (diet, exercise, smoking cessation). Biological factors are also suggested, including altered autonomic nervous system activity with elevations in catecholamine levels and inflammatory responses amongst others (3). Similar hypotheses have been put forth regarding the mechanism of takotsubo stress cardiomyopathy and perhaps some overlap exists between the cardiovascular manifestations of psychiatric disorders and overt stress cardiomyopathy.The COVID-19 pandemic has had several medical consequences beyond those related to viral infection itself. The suspension of certain medical and surgical services potentially allows for the natural history of various diseases to take their course. Unemployment impairs the ability of many to access what medical services remain available. Psychiatric disorders are inflamed in the setting of social, economic, and other stressors. A four to five-fold increase in the incidence of stress cardiomyopathy has been noted during the months following the COVID-19 outbreak unrelated to COVID-19 infection itself, presumably the consequence of stress related to the abovementioned effects of the pandemic and our response to it. (4). COVID-19 has taught us that stress kills.REFERENCESKir D, Beer N, De Marchena EJ. Takutsobo cardiomyopathy caused by emotional stressors in the Coronavirus Disease 2019 (COVID-19) pandemic era. J Card Surg in pressDe Chazal HM, Del Buono MG, Keyser-Marcus L, Ma L, Moeller FG, Berrocal D, Abbate A. Stress cardiomyopathy diagnosis and treatment. J Am Coll Cardiol 2018;72:1955-71Takagi H, Ando T, Umemoto. Perioperative depression or anxiety and postoperative mortality in cardiac surgery: a systematic review and meta-analysis. Heart Vessels 2017;32:1458-1468Jabri A, Kalra a, Kumar A, Alameh A, Adroja S, Bashir H, Nowacki AS, Shah R, Khubber S, Kanaa’N A, Hedrick DP, Sleik KM, Mehta N, Chung MK, Khot UN, Kapadia SR, Puri R, Reed GW. Incidence of stress cardiomyopathy during the coronavirus disease 2019 pandemic. JAMA Netw Open 2020 Jul 1;3(7):e2014780. doi: 10.1001/jamanetworkopen.2020.14780

Dimitrios Vlastos

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Background The coronavirus-disease 2019 (COVID-19) pandemic imposed an unprecedented burden on the provision of cardiac surgical services. The reallocation of workforce and resources necessitated the postponement of elective operations in this cohort of high-risk patients. We investigated the impact of this outbreak on the aortic valve surgery activity at a single two-site centre in the United Kingdom. Methods and Results Data were extracted from the local surgical database, including the demographics, clinical characteristics, and outcomes of patients operated on from March 2020 to May 2020 and compared with the respective 2019 period. The experience of centres world-wide was invoked to assess the efficiency of our services. There was a 38.2% reduction in the total number of operations with a 70% reduction in elective cases, compared with a 159% increase in urgent and emergency operations. The attendant surgical risk was significantly higher [median Euroscore II was 2.7 [1.9-5.2] in 2020 versus 2.1 [0.9-3.7] in 2019 (p=0.005)] but neither 30-day survival nor freedom from major post-operative complications (re-sternotomy for bleeding/tamponade, transient ischemic attack/stroke, renal replacement therapy) was compromised (p>0.05 for all comparisons). Conclusion RBHT managed to offer a considerable volume of aortic valve surgical activity over the first COVID-19 outbreak to a cohort of higher-risk patients, without compromising post-operative outcomes. A backlog of elective cases is expected to develop, the accommodation of which after surgical activity normalisation will be crucial to monitor.

Yanjuan Zhang

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Chavin Naotunna

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The sinoatrial node in medication-resistant inappropriate sinus tachycardia: to modify or to ablate?Khalil El Gharib1*1Hôtel-Dieu de France, Beirut, Lebanon*Author for correspondence: khalil.gharib@outlook.comKEYWORDS: IST, sinus node modification, sinus node ablation, radiofrequency ablation, surgical ablationNo conflict of interest to discloseFunding: noneInappropriate sinus tachycardia (IST) is defined as a resting heart rate >100 beats per minute (with a mean heart rate >90 beats per minute over 24 hours) associated with highly symptomatic palpitations(1). The syndrome is associated neither with structural heart disease nor with any secondary cause of sinus tachycardia(2) and evidence suggests that enhanced intrinsic automaticity of the sinoatrial node, which can be due to anti-β-adrenergic antibodies, is behind its genesis(3). However, it is benign in terms of clinical outcomes and echocardiographic evidence of ventricular dysfunction(4), being rarely associated with tachycardia-induced cardiomyopathy(3).Patients with IST are essentially treated with ß-blockers to alleviate their symptoms(5). Ivabradine, a drug that inhibits funny calcium channels, particularly abundant in the SA node, showed modest benefit, receiving class IIa recommen­dation in the treatment of IST(4). But, the duration of medical therapy might be indefinite, and, a considerable number of patients would respond inadequately, or have no response, even after prolonged therapy(5). Historically, such patients would have subtotal right atrial excision, atrioventricular junctional ablation with permanent pacemaker implantation, or chemical occlusion of the sinus node artery(6). These options are considered today unacceptable in this setting, and other therapeutic approaches should be unveiled when resistance to medical treatment appears.Electrophysiological study was initially purely diagnostic, but recent advances in technology have allowed us to intervene(7); patients with ventricular and supraventricular tachyarrhythmias are successfully treated with percutaneous catheter procedures. Of these, SA node ablation/ modification has been proposed as alternative approaches in IST that is not responding to medical treatment; trials reported auspicious results, highlighted here.Electrophysiologic mapping to the site of the earliest endocardial activation during either spontaneous sinus tachycardia or isoproterenol-induced sinus tachycardia has rendered these procedures feasible(8). Additionally, combination with intracardiac echocardiography permitted a more accurate electrophysiologic and anatomic localization of the sinoatrial node(9).Sinus node modification is not a focal ablation, but requires complete abolition of the cranial portion of the SA node complex, the one that exhibits the most of the autonomic activity(9). It is defined as successful when the heart rate decreases by 30 beats per minute (bpm) during isoproterenol infusion(8). Short-term success was also defined by other investigators when there was a reduction of the baseline sinus rate to less than 90 bpm and the sinus rate during isoproterenol infusion by more than 20% or by 25%(8). The acute success rate for modification has been varying between 76 and 100 % across trials, while long-term clinical outcomes are modest at best, with reported freedom from IST ranging from 23 to 85%(10).Complications specific to SA node modification include superior vena cava (SVC) syndrome, diaphragmatic paralysis, and sinus node dysfunction(10). And while modification with conventional methods has its setbacks, modification using laser energy can be considered in the setting of IST. This modality creates clear-cut homogenous transmural lesions of the myocardium that comprises the scattered “functional” SA node(11). The burnt myocardium will then heal into a dense fibrous scar, decreasing potential amplitudes. And when adapting laser energy settings to the thickness of the myocardial wall, collateral dam­ages such as esophageal fistulae, lung burns, and phrenic nerve palsy will be avoided(11); thus, this technique may prove itself as a new intriguing alternative for the safe and effective treatment of IST.SA node modification is apt in achieving acute reductions in postprocedural heart rate. However, and as aforementioned, success rates are suboptimal in terms of symptomatic control with a significant recurrence rate(12). Catheter ablation aiming at either total exclusion and obliteration of the SA node has been described and performed, success being defined as a slowing of >50% from the baseline rate of tachycardia along with a junctional escape rhythm(12). With radiofrequency (RF) applications, the earliest local atrial activation time would shift from a cranial location to a more caudal one, usually at the mid-lateral right atrium(5). Reviews have reported that acute success rates were consistently to be as high as 88.9%, with an overall frequency of recurrence of 19.6%, the latter occurring within a wide range of post-ablation intervals, anywhere from a few weeks to several months after the procedure(12). Additionally, Takemoto and colleagues documented a significant drop in B-type natriuretic peptide levels, 6 to 12 months after ablation, suggesting fewer stretching shears on cardiac muscle.Two types of response of the sinus tachycardia to RFA were observed across studies, whether a step-wise reduction in sinus rate accompanying migration of the site of earliest atrial activation in a cranial-caudal direction along the lateral right atrial wall, or an abrupt drop in heart rate in response to RFA at a focal site of earliest atrial activation(13).However, RFA of inappropriate sinus tachycardia requires a large number of applications of radiofrequency energy and is, as in SA node modification, associated with a high recurrence rate(13). Complete remission is achieved only in approximately 50% of patients in some studies(14); longer history of IST and those reporting near syncope/syncope having a higher probability of recurrence(15).While other studies have shown that RF ablation of the SA node can achieve even longer-term reductions in the sinus rate and relief of symptoms in two-thirds of patients with drug-refractory, inappropriate sinus tachycardia(13), aiming specific sites related to the SA node should be elaborated, for better and optimal outcomes Killu and colleagues created a lesion in the arcuate ridge resulting in complete abolition of the tachycardia, since arrhythmias arising in this region may exhibit both electrocardiographic and clinical similarities to IST(16). This has led to consider ablation of the arcuate ridge as a treatment of refractory IST, necessitating larger trials to confirm its potential role.Phrenic nerve injury is a severe and dreaded complication of SN ablation(12). Pericarditis, right diaphragmatic paralysis, and SVC syndrome are other undesirable side effects of the procedures, variously reported in studies. but a common complication was observed in them all, atrial tachyarrhythmias(12). It has been hypothesized that myocardial pathology, such as inflammation and fibrosis, considered iatrogenic due to the ablation procedures, may be promoting arrhythmias both in the region of the SA node, as well as in remote locations(12). Through multivariable analysis, higher resting heart rates post-ablation and smaller cranial-to-caudal shifts have been defined as predictors of atrial arrhythmias(15). In conclusion, catheter ablation could be considered an effective treatment for highly symptomatic, drug-refractory patients, even for those who did not respond to SA node modification(5).The sinus node is located close to the epicardial surface and catheter-based ablations do not always make full-thickness lesions across the atrial muscle, leading to failure of the ablation(17), besides the numerous trabeculae and the widely variable anatomy.Surgical ablation is not a first-line or routine management strategy for IST, but it has been proposed when IST resists or recurs after SN modification/ endocardial ablation(17). Effectively, in several studies, epicardial lesions, through a single small incision in one of the intercostal spaces, successfully slowed heart rate and shifted activation to a more caudal location, and surprisingly, subsequent endocardial lesions led to an even greater drop in heart rate and more caudal site of earliest activation(18). These outcomes were again replicated when using minimally invasive thoracoscopic ablation of the epicardial site of the SA node, concluding of the promising efficacy and the safety of this approach, since it preserves the phrenic nerve(17), although continued follow-up after surgery is required.Medication-resistant IST remains a medical challenge for physicians and cardiologists; and in the era of great advances in interventional cardiology, its treatment remains debatable. Sinus node modification/ ablation is not recommended as first-line therapy in IST, this procedure should be considered only in drug-refractory patients who have severe symptoms(13). Although the number of patients in the available studies is generally small, both procedures have documented an encouraging success rate in the short-term, while being less impressive in the long-term. It has been hypothesized that this discrepancy is due to the relatively large potential area of atrial pacemaker cells(18); modification or ablation may fail to ablate or isolate all the pathways that comprise the functional SA node because they often target the anatomic part and the area of earliest atrial activation(19). Others have explained that the long-term slowing in rhythm fails because these procedures inconsistently produce transmural lesions in the right atrium. Surgical treatment of IST has proposed a solution to the latter conflict when isolating the SA node with a wide cuff of surrounding atrial muscle(19). And with the advent of bipolar RF clamps and minimally invasive cardiac surgical techniques with thoracoscopic guidance, this approach appears more appealing than before, especially when combined with endocardial ablation(19). But again, current data specifies employing these techniques in highly selected cases.


and 10 more

Background: There is insufficient evidence regarding the comparison of Rapid Deployment aortic valve replacement(RDAVR) to TAVR in intermediate-risk patients with severe symptomatic aortic stenosis(AS) Aims: We compare the 2-years outcomes between RDAVR with INTUITY and TAVR with SAPIEN 3 in intermediate-risk patients with AS. Methods: Inclusion criteria: severe AS implanted with RDAVR or TAVR; EUROSCORE II ≥ 4% and clinical evaluation by Heart Team. Regression adjustment for the propensity score was used to compare RDAVR with TAVR(1:1). Primary endpoint: composite criterion of death, disabling stroke or rehospitalization. Secondary endpoints: occurrence of major bleeding post-operative complications, paravalvular regurgitation (PVR)≥2 and patient-prosthesis mismatch(PPM) at 1 month and pacemaker implantation at 2 years. Results: A total of 152 patients were included from 2012 to 2018: 48 in the RDAVR group and 104 in the TAVR group. Mean age was 82.7±6, 51.3% were female, mean Euroscore II was 6.03±1.6% and mean baseline LVEF was 56±13%,mean indexed iEOA was 0.41±0.1cm/m2, mean gradient was 51.7±14.7mmHg. Patients with RDAVR were younger(79.5±6vs82.6±6,p=0.01), at higher risk (EUROSCORE2 6,61±1,8%vs5,63±1,5%, p=0.005), combined surgery was performed in 28 patients(58.3%). Twenty-two patients(45.99%) met the primary outcome in the RDAVR group and 32 patients(66.67%) in the TAVR group. By 1:1propensity score matching analysis, there was a significant difference between both groups in favor of RDAVR(HR=0.58[95%CI:0.34;1.00],p=0.04). No difference were observed in PPM occurrence(0.83;[0.35-1.94];p=0.67),major bleeding events(1.33;[0.47-3.93];p=0.59),PVR≥2(0.33[0-6.28],p=0.46), and pacemaker implantation (0.84[0.25-2.84],p=0.77).Conclusion: RDAVR is associated with better 2-years outcomes than TAVR in intermediate-risk patients with severe symptomatic AS.

Francesca Mori

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