Sudden cardiac death in patients with aortic stenosis: maybe it is not the valve?

Numerical simulation of the blood flow through a pre-stenotic aneurysm in coronary artery: effects of varying heart rate

The left anterior descending artery (LAD) is a significant coronary artery and a facilitator of oxygenated blood to the heart muscles. Thus, any occurrence of an aneurysm in LAD requires immediate medical attention. It is often inclined toward fatality if coupled with a blockage due to stenosis. Given the high relevance of understanding such models, invasive techniques under all parametric circumstances are hard to achieve. So, a theoretical approach with a cost-effective intervention of mathematical modeling becomes essential. In our current work, we analyze the model with the numerical technique of a modified form of SIMPLE pressure-correction based algorithm and perform parametric studies for the flow field with degree of stenosis, degree of aneurysm, heart rate, and distance separating aneurysm and stenosis as parameters. The study reveals a direct proportionality relation between the number of recirculation zones and heart rate through instantaneous streamline plots. Alongside this, the demonstration of an increase in the risk of rupture of the aneurysm with a decrease in the distance between stenosis and aneurysm, using the physical parameters associated with blood flow, is another key finding. Further, we examine the effect of the flow field on heat transfer and the consequent temperature profiles.

Recurrence of syncope after valve replacement in severe aortic stenosis

OBJECTIVE

The recurrence of syncope after valve intervention in severe aortic stenosis (SAS) and its impact on outcome are unknown. We hypothesised that syncope on exertion will disappear after intervention, whereas syncope at rest might recur. Our aim has been to describe the recurrence of syncope in patients with SAS undergoing valve replacement and its impact on mortality.

METHODS

Double-centre observational registry of 320 consecutive patients with symptomatic SAS without other valve disease and/or coronary artery disease who underwent valve intervention and were discharged alive. All-cause mortality and cardiovascular mortality were considered events.

RESULTS

53 patients (median age 81 years, 28 men) had syncope (29 on exertion, 21 at rest, 3 unknown). Clinical and echocardiographic variables were similar in patients with and without syncope (median vmax 4.44 m/s, mean gradient 47 mm Hg, valve area 0.7 cm2, left ventricular ejection fraction 62%). After a median follow-up of 69 months (IQR: 55-88), syncope on exertion did not recur in any patient. In contrast, 8 of the 21 patients with syncope at rest had postintervention syncope at rest (38%; p<0.001): 3 needed a pacemaker, 3 were neuromediated or hypotensive and 2 arrhythmic. Only recurrence of syncope was associated with cardiovascular mortality (HR 5.74; 95% CI 2.17 to 15.17; p<0.001).

CONCLUSIONS

Syncope on exertion in patients with SAS did not recur after aortic valve intervention. Syncope at rest recurs in a high proportion of patients and identifies a population with increased mortality. According to our results, syncope at rest should be thoroughly evaluated before proceeding to aortic valve intervention.

Left-sided valvular heart disease and survival in out-of-hospital cardiac arrest: a nationwide registry-based study

Survival in left-sided valvular heart disease (VHD; aortic stenosis [AS], aortic regurgitation [AR], mitral stenosis [MS], mitral regurgitation [MR]) in out-of-hospital cardiac arrest (OHCA) is unknown. We studied all cases of OHCA in the Swedish Registry for Cardiopulmonary Resuscitation. All degrees of VHD, diagnosed prior to OHCA, were included. Association between VHD and survival was studied using logistic regression, gradient boosting and Cox regression. We studied time to cardiac arrest, comorbidities, survival, and cerebral performance category (CPC) score. We included 55,615 patients; 1948 with AS (3,5%), 384 AR (0,7%), 17 MS (0,03%), and 704 with MR (1,3%). Patients with MS were not described due to low case number. Time from VHD diagnosis to cardiac arrest was 3.7 years in AS, 4.5 years in AR and 4.1 years in MR. ROSC occurred in 28% with AS, 33% with AR, 36% with MR and 35% without VHD. Survival at 30 days was 5.2%, 10.4%, 9.2%, 11.4% in AS, AR, MR and without VHD, respectively. There were no survivors in people with AS presenting with asystole or PEA. CPC scores did not differ in those with VHD compared with no VHD. Odds ratio (OR) for MR and AR showed no difference in survival, while AS displayed OR 0.58 (95% CI 0.46-0.72), vs no VHD. AS is associated with halved survival in OHCA, while AR and MR do not affect survival. Survivors with AS have neurological outcomes comparable to patients without VHD.

Association of Mortality With Aortic Stenosis Severity in Outpatients: Results From the VALVENOR Study

Importance

Modern data regarding incidence and modes of death of patients with aortic stenosis (AS) are restricted to tertiary centers or studies of aortic valve replacement (AVR).

Objective

To provide new insights into the natural history of outpatients with native AS based on a large regionwide population study with inclusion by all cardiologists regardless of their mode of practice.

Design, Setting, and Participants

Between May 2016 and December 2017, consecutive outpatients with mild (peak aortic velocity, 2.5-2.9 m/s), moderate (peak aortic velocity, 3-3.9 m/s), and severe (peak aortic velocity, ≥4 m/s) native AS graded by echocardiography were included by 117 cardiologists from the Nord-Pas-de-Calais region in France. Analysis took place between August and November 2020.

Main Outcomes and Measures

Natural history, need for AVR, and survival of patients with AS were followed up. Indications for AVR were based on current guideline recommendations.

Results

Among 2703 patients (mean [SD] age, 76.0 [10.8] years; 1260 [46.6%] women), 233 (8.6%) were recruited in a university public hospital, 757 (28%) in nonuniversity public hospitals, and 1713 (63.4%) by cardiologists working in private practice. A total of 1154 patients (42.7%) had mild, 1122 (41.5%) had moderate, and 427 (15.8%) had severe AS. During a median (interquartile range) of 2.1 (1.4-2.7) years, 634 patients underwent AVR and 448 died prior to AVR. Most deaths were cardiovascular (200 [44.7%]), mainly associated with congestive heart failure (101 [22.6%]) or sudden death (60 [13.4%]). Deaths were noncardiovascular in 186 patients (41.5%) and from unknown causes in 62 patients (13.8%). Compared with patients with mild AS, there was increased cardiovascular mortality in those with moderate (hazard ratio, 1.47 [95% CI, 1.07-2.02]) and severe (hazard ratio, 3.66 [95% CI, 2.52-5.31]) AS. The differences remained significant when adjusted for baseline characteristics or in time-dependent analyses considering AS progression. In asymptomatic patients, moderate and mild AS were associated with similar cardiovascular mortality (hazard ratio, 0.99 [95% CI, 0.44-2.21]).

Conclusions and Relevance

While patients in this study with moderate AS had a slightly higher risk of cardiovascular death than patients with mild AS, this risk was much lower than that observed in patients with severe AS. Moreover, in asymptomatic patients, moderate and mild AS were associated with similar cardiovascular mortality.

The impact of COVID-19 pandemic on aortic valve surgical service: a single centre experience

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

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 with only one of the two sites resuming operative activity and compared with the respective 2019 period. A similar comparison was conducted with the period between June 2020 and August 2020, when operative activity was restored at both institutional sites. The experience of centres world-wide was invoked to assess the efficiency of our services.

Results

There was an initial 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). Recommencement of activity at both institutional sites conferred a surgical volume within 17% of the pre-COVID-19 era.

Conclusions

Our institution 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.

Management of aortic stenosis: a systematic review of clinical practice guidelines and recommendations

Multiple guidelines exist for the management of aortic stenosis (AS). We systematically reviewed current guidelines and recommendations, developed by national or international medical organizations, on management of AS to aid clinical decision-making. Publications in MEDLINE and EMBASE between 1 June 2010 and 15 January 2021 were identified. Additionally, the International Guideline Library, National Guideline Clearinghouse, National Library for Health Guidelines Finder, Canadian Medical Association Clinical Practice Guidelines Infobase, and websites of relevant organizations were searched. Two reviewers independently screened titles and abstracts. Two reviewers assessed rigour of guideline development and extracted the recommendations. Of the seven guidelines and recommendations retrieved, five showed considerable rigour of development. Those rigourously developed, agreed on the definition of severe AS and diverse haemodynamic phenotypes, indications and contraindications for intervention in symptomatic severe AS, surveillance intervals in asymptomatic severe AS, and the importance of multidisciplinary teams (MDTs) and shared decision-making. Discrepancies exist in age and surgical risk cut-offs for recommending surgical aortic valve replacement (SAVR) vs. transcatheter aortic valve implantation (TAVI), the use of biomarkers and complementary multimodality imaging for decision-making in asymptomatic patients and surveillance intervals for non-severe AS. Contemporary guidelines for AS management agree on the importance of MDT involvement and shared decision-making for individualized treatment and unanimously indicate valve replacement in severe, symptomatic AS. Discrepancies exist in thresholds for age and procedural risk used in choosing between SAVR and TAVI, role of biomarkers and complementary imaging modalities to define AS severity and risk of progression in asymptomatic patients.