Degenerative Severe Aortic Stenosis and Concomitant Coronary Artery Disease: What Is Changing in the Era of the "Transcatheter Revolution"?

Age Differences in Aortic Stenosis

Aortic stenosis (AS) is a significant and growing concern, with a prevalence of 2-3% in individuals aged over 65 years. Moreover, with an aging global population, the prevalence is anticipated to double by 2050. Indeed, AS can arise from various etiologies, including calcific trileaflets, congenital valve abnormalities (e.g., bicuspid and unicuspid valves), and post-rheumatic, whereby each has a distinct influence that shapes the onset and progression of the disease. The normal aortic valve has a trilaminar structure comprising the fibrosa, spongiosa, and ventricularis, which work together to maintain its function. In calcific AS, the disease begins with early calcification starting in high mechanical stress areas of the valve and progresses slowly over decades, eventually leading to extensive calcification resulting in impaired valve function. This process involves mechanisms similar to atherosclerosis, including lipid deposition, chronic inflammation, and mineralization. The progression of calcific AS is strongly associated with aging, with additional risk factors including male gender, smoking, dyslipidemia, and metabolic syndrome exacerbating the condition. Conversely, congenital forms of AS, such as bicuspid and unicuspid aortic valves, result in an earlier disease onset, typically 10-20 years earlier than that observed in patients with a normal tricuspid aortic valve. Rheumatic AS, although less common in developed countries due to effective antibiotic treatments, also exhibits age-related characteristics, with an earlier onset in individuals who experienced rheumatic fever in their youth. The only curative therapies currently available are surgical and transcatheter aortic valve replacement (TAVR). However, these options are sometimes too invasive for older patients; thus, management of AS, particularly in older patients, requires a comprehensive approach that considers age, disease severity, comorbidities, frailty, and each patient's individual needs. Although the valves used in TAVR demonstrate promising midterm durability, long-term data are still required, especially when used in younger individuals, usually with low surgical risk. Moreover, understanding the causes and mechanisms of structural valve deterioration is crucial for appropriate treatment selections, including valve selection and pharmacological therapy, since this knowledge is essential for optimizing the lifelong management of AS.

Transcatheter aortic valve replacement outcomes in patients with high gradient versus low ejection fraction low gradient severe aortic stenosis: A meta-analysis of randomized controlled trials

BACKGROUND

The outcome of Low Flow-Low Gradient (LF-LG) severe aortic stenosis (AS) patients who underwent Transcatheter Aortic Valve Replacement (TAVR) procedure is not well defined. We conducted a systematic review of the literature to compare the outcomes of TAVR in LF-LG AS patients to the more traditional high gradient (HG) aortic stenosis.

METHODS

We comprehensively searched for controlled randomized and non-randomized studies from 4 online databases. We are presenting the data using risk ratios (95 % confidence intervals) and measuring heterogeneity using Higgins' I2 index.

RESULTS

Our analysis included 4380 patients with 3425 HG patients and 955 LF-LG patients from 6 cohort (5 retrospective and 1 prospective) studies. When compared to LFLG; TAVR was associated with significantly lower 30 days mortality in HG patients (5.1 % vs 7.4 %; relative risk [RR]: 0.55; 95 % confidence interval [CI]: 0.35 to 0.86; p < 0.01). Similar findings were also observed in 12-month cardiovascular (CV) mortality (5.5 % vs. 10.4 %; RR: 0.47; 95 % CI: 0.38 to 0.60; p < 0.01 and 12-month all-cause mortality (15.9 % vs 20.9 %; RR: 0.70; 95 % CI: 0.49 to 1.00; p < 0.05). There was no significant difference in myocardial infarction (MI) after TAVR between HG and LF-LG at 30 days (0.16 % vs. 0.95 %; p < 0.09) or 12 months (0.43 % vs. 0.95 %; p = 0.20). Similarly, there was no difference in stroke rates at 30 days (2.9 % vs. 2.86 %) or at 12 months (3.6 % vs. 3.06 %).

CONCLUSIONS AND RELEVANCE

Patients with LF-LG severe AS who underwent TAVR had worse 1-year all-cause mortality, 30-day all-cause, and 1-year CV mortality when compared to TAVR in HG severe AS. There was no difference in MI or stroke rates. Therefore, with heart team discussion and informed patient decision regarding the risk and benefit, TAVR would still offer better outcomes in LFLG AS compared to conservative medical management.

Atherosclerosis, calcific aortic valve disease and mitral annular calcification: same or different?

There are similarities in the pathophysiologic mechanisms of atherosclerosis, calcific aortic valve disease (CAVD) and mitral annular calcification (MAC), however, medical treatment to slow or stop the progression of CAVD or MAC has been more elusive as compared to atherosclerosis. Atherosclerosis and CAVD share common demographic, clinical, protein, and genetic factors even more so than with MAC, which supports the possibility of shared medical therapies, though abrogating calcific extracellular vesicle shedding could be a common target for all three conditions. Herein, we summarize the overlapping and distinct pathways for further investigation, as well as key areas where additional research is needed.

Comparison of the outcomes of concurrent versus staged TAVR combined with PCI in patients with severe aortic stenosis and coronary artery disease: a systematic review and meta-analysis

BACKGROUND

The optimal timing for percutaneous coronary intervention (PCI) in patients undergoing transcatheter aortic valve replacement (TAVR) remains uncertain. This research aims to evaluate the results of patients diagnosed with severe aortic valve stenosis and coronary artery disease who undergo either simultaneous or staged PCI therapy during TAVR procedures.

METHODS

We retrieved all relevant studies from our self-constructed databases up to January 2, 2024, encompassing databases such as Embase, Medline, Cochrane Library, and PubMed.

RESULTS

A total of nine studies were included, and the results showed that both surgical modalities had good safety profiles in the early and long-term stages. For early endpoint events, the risk of all-cause mortality and major bleeding within 30 years was similar in the staged TAVR + PCI and the contemporaneous TAVR + PCI ( P > 0.05). Additionally, the risk of myocardial infarction, stroke, acute kidney injury and pacemaker implantation within 30 days or perioperatively is similar ( P > 0.05). For long-term endpoint events, the risk of all-cause mortality, myocardial infarction and stroke was similar in the two groups at ≥2 years ( P > 0.05).

CONCLUSION

In patients undergoing TAVR who required coronary revascularization, no significant differences were observed in the early and long-term outcomes between those receiving concurrent TAVR and PCI versus staged surgery.

Evaluation of Instantaneous Wave-Free Ratio and Fractional Flow Reserve in Severe Aortic Valve Stenosis

BACKGROUND

The optimal functional evaluation of coronary artery stenosis in patients with severe aortic stenosis (AS) has not been established. The objective of the study was to evaluate the instantaneous wave-free ratio (iFR) and fractional flow reserve (FFR) in patients with and without severe AS.

METHODS

We retrospectively investigated 395 lesions in 293 patients with severe AS and 2257 lesions in 1882 patients without severe AS between 2010 and 2022 from a subgroup of the Interventional Cardiology Research In-Cooperation Society FFR Registry. All patients had FFR values, and iFR was analyzed post hoc using dedicated software only in lesions with adequate resting pressure curves (311 lesions in patients with severe AS and 2257 lesions in patients with nonsevere AS).

RESULTS

The incidence of iFR ≤0.89 was 66.6% and 31.8% (P<0.001), while the incidence of FFR ≤0.80 was 45.3% and 43.9% (P=0.60) in the severe AS group and the nonsevere AS group, respectively. In the severe AS group, most lesions (95.2%) with iFR >0.89 had FFR >0.80, while 36.2% of lesions with iFR ≤0.89 had FFR >0.80. During a median follow-up of 2 years, FFR ≤0.80 was significantly associated with deferred lesion failure (adjusted hazard ratio, 2.71 [95% CI, 1.08-6.80]; P=0.034), while iFR ≤0.89 showed no prognostic value (adjusted hazard ratio, 1.31 [95% CI, 0.47-3.60]; P=0.60) in the severe AS group. Lesions with iFR ≤0.89 and FFR >0.80, in particular, were not associated with a higher rate of deferred lesion failure at 3 years compared with lesions with iFR >0.89 (15.4% versus 17.0%; P=0.58).

CONCLUSIONS

This study suggested that FFR appears to be less affected by the presence of severe AS and is more associated with prognosis. iFR may overestimate the functional severity of coronary artery disease without prognostic significance, yet it can be useful for excluding significant stenosis in patients with severe AS.

Electrocardiography versus Echocardiography in Severe Aortic Stenosis with the Consideration of Coexistent Coronary Artery Disease

(1) Background: Coexistent coronary artery disease (CAD) might influence the ability of electrocardiogram (ECG) to identify echocardiographic left ventricular hypertrophy (ECHO-LVH) in patients with aortic stenosis (AS). We aimed to assess the relation between ECG-LVH (by the Sokolov-Lyon or Cornell criteria) and ECHO-LVH considering coexistent CAD. (2) Methods: We retrospectively analyzed the medical records of 74 patients (36 males) with severe AS who were hospitalized in the University Hospital in Cracow from 2021 to 2022. (3) Results: ECHO-LVH was present in 49 (66%) patients, whereas 35 (47.3%) patients had ECG-LVH. There was no difference between the rate of ECG-LVH in patients with vs. without ECHO-LVH. Single-vessel and multi-vessel CAD were diagnosed by invasive coronary angiography in 18% and 11% of patients, respectively. The sensitivity of the classical ECG-LVH criteria with regard to ECHO-LVH was low, reaching at best 41% for the Sokolov-Lyon and Cornell criteria. The results were similar and lacked a pattern when considering patients without significant stenosis, with single- and multi-vessel disease separately. Correlations between the left ventricular mass index and ECG-derived parameters were weak and present solely for the Lewis index (r = 0.31), R wave's amplitude >1.1 mV in aVL (r = 0.36), as well as the Cornell (r = 0.32) and Sokolov-Lyon (r = 0.31) voltage criteria (p < 0.01). The presence, location of stenoses, and CAD extent were not associated with the presence of either ECHO-LVH or ECG-LVH, irrespective of individual ECG-LVH criteria. (4) Conclusions: The sensitivity of classical ECG criteria for echocardiographic LVH in severe AS is low, regardless of coexistent CAD or its angiographic extent.

Angina in patients with severe aortic stenosis undergoing transcatheter aortic valve replacement

INTRODUCTION AND OBJECTIVES

To evaluate the prevalence, clinical characteristics, and outcomes of patients with angina undergoing transcatheter aortic valve replacement (TAVR) for severe aortic stenosis.

METHODS

A total of 1687 consecutive patients with severe aortic stenosis undergoing TAVR at our center were included and classified according to patient-reported angina symptoms prior to the TAVR procedure. Baseline, procedural and follow-up data were collected in a dedicated database.

RESULTS

A total of 497 patients (29%) had angina prior to the TAVR procedure. Patients with angina at baseline showed a worse New York Heart Association (NYHA) functional class (NYHA class> II: 69% vs 63%; P=.017), a higher rate of coronary artery disease (74% vs 56%; P <.001), and a lower rate of complete revascularization (70% vs 79%; P <.001). Angina at baseline had no impact on all-cause mortality (HR, 1.02; 95%CI, 0.71-1.48; P=.898) and cardiovascular mortality (HR, 1.2; 95%CI, 0.69-2.11; P=.517) at 1 year. However, persistent angina at 30 days post-TAVR was associated with increased all-cause mortality (HR, 4.86; 95%CI, 1.71-13.8; P=.003) and cardiovascular mortality (HR, 20.7; 95%CI, 3.50-122.6; P=.001) at 1-year follow-up.

CONCLUSIONS

More than one-fourth of patients with severe aortic stenosis undergoing TAVR had angina prior to the procedure. Angina at baseline did not appear to be a sign of a more advanced valvular disease and had no prognostic impact; however, persistent angina at 30 days post-TAVR was associated with worse clinical outcomes.

Impact of Chronic Coronary Artery Disease and Revascularization Strategy in Patients with Severe Aortic Stenosis Who Underwent Transcatheter Aortic Valve Implantation

The prognostic impact of coronary artery disease (CAD) after transcatheter aortic valve implantation (TAVI) is controversial. The aim of this study is to investigate the impact of CAD and different revascularization strategies on clinical outcomes in patients who underwent TAVI with third generation devices. Patients enrolled in the national observational Observational Study of Effectiveness of SAVR-TAVI Procedures for Severe Aortic Stenosis Treatment II study were stratified according to the presence of CAD (CAD+, n = 1,130) versus no CAD (CAD-, n = 1,505), and compared using a propensity matched analysis. CAD+ group was further stratified according to the revascularization strategy: no revascularization (n = 331), revascularization performed >90 days before index-TAVI (n = 417) and coronary revascularization performed <90 days before index-TAVI or during TAVI (n = 382). In-hospital, 30-day and 1-year clinical outcomes were estimated. The mean age of the overall population was 81.8 years; 54.9% of patients were female. Propensity score matching yielded 813 pairs and their 30-day all-cause mortality was comparable (p = 0.480). Major periprocedural adverse events were also similar between the groups. At 1-year follow-up, the rate of major adverse cardiac and cerebrovascular events (MACCEs) and all-cause mortality were similar between the groups (p = 0.732 and p = 0.633, respectively). Conversely, patients with CAD experienced more often myocardial infarction and need for percutaneous coronary intervention at 1 year (p = 0.007 and p = 0.001, respectively). Neither CAD nor revascularization strategy were independent predictors of 1-year MACCE. About 40% of patients presenting with severe AS and who underwent TAVI had concomitant CAD. The presence of CAD had no impact on all-cause mortality and MACCE 1-year after TAVR. However, CAD carries a higher risk for acute myocardial infarction and need of percutaneous coronary intervention during follow-up.

Anesthetic management with remimazolam in very elderly patients undergoing hybrid surgery of transcatheter aortic valve implantation plus off-pump coronary artery bypass grafting: report of two cases

BACKGROUND

Remimazolam is a short-acting benzodiazepine with small circulatory depression. We used remimazolam for general anesthesia management in two very elderly patients undergoing hybrid surgery of transcatheter aortic valve implantation (TAVI) plus off-pump coronary artery bypass grafting (OPCABG).

CASE PRESENTATION

A 96-year-old man (case 1) and a 92-year-old woman (case 2) had complex coronary artery disease (CAD) and severe aortic stenosis (AS) and were scheduled for TAVI plus OPCAB. Anesthesia in both patients was induced with 6 mg/kg/h remimazolam and fentanyl and maintained with 0.3 mg/kg/h and 0.5 mg/kg/h remimazolam and fentanyl, respectively. Although catecholamines were required, we successfully maintained circulation during the induction of anesthesia and the procedures of OPCAB and TAVI. Both patients were discharged without complications.

CONCLUSION

Remimazolam can be a useful option for safe general anesthesia in very elderly patients when performing hybrid surgery.

Invasive Functional Assessment of Coronary Artery Disease in Patients with Severe Aortic Stenosis in the TAVI Era

Coronary artery disease (CAD) is a common finding in patients suffering from aortic valve stenosis (AS), with a prevalence of over 50% in patients 70 years of age or older. Transcatheter aortic valve intervention (TAVI) is the standard treatment option for patients with severe AS and at least 75 years of age. Current guidelines recommend percutaneous coronary intervention (PCI) in patients planned for TAVI with stenoses of >70% in the proximal segments of non-left main coronary arteries and in >50% of left main stenoses. While the guidelines on myocardial revascularization clearly recommend functional assessment of coronary artery stenoses of less than 90% in the absence of non-invasive ischemia testing, a statement regarding invasive functional testing in AS patients with concomitant CAD is lacking in the recently published guideline on the management of valvular heart disease. This review aims to provide an overview of the hemodynamic background in AS patients, discusses and summarizes the current evidence of invasive functional testing in patients with severe AS, and gives a future perspective on the ongoing trials on that topic.

Aortic Stenosis Phenotypes and Precision Transcatheter Aortic Valve Implantation

Patients with a clinical indication for aortic valve replacement can either undergo surgical aortic valve replacement (SAVR) or Transcatheter Aortic Valve Implantation (TAVI). There are many different factors that go into determining which type of replacement to undergo, including age, life expectancy, comorbidities, frailty, and patient preference. While both options offer significant benefits to patients in terms of clinical outcomes and quality of life, there is growing interest in expanding the indications for TAVI due to its minimally invasive approach. However, it is worth noting that there are several discrepancies in TAVI outcomes in regards to various endpoints, including death, stroke, and major cardiovascular events. It is unclear why these discrepancies exist, but potential explanations include the diversity of etiologies for aortic stenosis, complex patient comorbidities, and ongoing advancements in both medical therapies and devices. Of these possibilities, we propose that phenotypic variation of aortic stenosis has the most significant impact on post-TAVI clinical outcomes. Such variability in phenotypes is often due to a complex interplay between underlying comorbidities and environmental and inherent patient risk factors. However, there is growing evidence to suggest that patient genetics may also play a role in aortic stenosis pathology. As such, we propose that the selection and management of TAVI patients should emphasize a precision medicine approach.

Percutaneous Coronary Intervention Pre-TAVR: Current State of the Evidence

PURPOSE OF REVIEW

This review intends to give an up-to-date overview of the current state of evidence in the treatment of coronary artery disease (CAD) in patients undergoing transcatheter aortic valve replacement (TAVR), focusing on percutaneous coronary interventions (PCI) pre-TAVR.

RECENT FINDINGS

The recently published ACTIVATION trial is the 1st randomized trial comparing coronary revascularization (PCI) versus medical treatment in patients with significant CAD undergoing TAVR. With the caveat of several major limitations of the trial, the results of this study raised the question about the appropriateness of the common practice to routinely revascularize coronary stenosis before TAVR. Aortic valve stenosis is the most common valvular heart disease among the elderly and it often co-occurs with CAD. TAVR is increasingly considered an alternative to surgical aortic valve replacement not only in the elderly population but also in younger and lower-risk patients. The impact of co-existing CAD on clinical outcomes as well as the optimal timing of PCI in TAVR candidates is still unclear and the subject of ongoing randomized trials. Meanwhile, it is common practice in many centers to routinely perform invasive coronary angiography and PCI for significant coronary disease as part of the TAVR workup. While computed tomography angiography has emerged as a possible alternative to the invasive coronary angiography in patients with low pre-test probability for CAD, the value of functional invasive assessment of coronary lesions in the pre-TAVR setting has still to be clarified. Also, there is an increasing interest in the clinical relevance and optimal management of the potentially challenging coronary access post-TAVR, requiring further research.

Challenges in Diagnosis and Functional Assessment of Coronary Artery Disease in Patients With Severe Aortic Stenosis

More than half of patients with severe aortic stenosis (AS) over 70 years old have coronary artery disease (CAD). Exertional angina is often present in AS-patients, even in the absence of significant CAD, as a result of oxygen supply/demand mismatch and exercise-induced myocardial ischemia. Moreover, persistent myocardial ischemia leads to extensive myocardial fibrosis and subsequent coronary microvascular dysfunction (CMD) which is defined as reduced coronary vasodilatory capacity below ischemic threshold. Therefore, angina, as well as noninvasive stress tests, have a low specificity and positive predictive value (PPV) for the assessment of epicardial coronary stenosis severity in AS-patients. Moreover, in symptomatic patients with severe AS exercise testing is even contraindicated. Given the limitations of noninvasive stress tests, coronary angiography remains the standard examination for determining the presence and severity of CAD in AS-patients, although angiography alone has poor accuracy in the evaluation of its functional severity. To overcome this limitation, the well-established invasive indices for the assessment of coronary stenosis severity, such as fractional flow reserve (FFR) and instantaneous wave-free ratio (iFR), are now in focus, especially in the contemporary era with the rapid increment of transcatheter aortic valve replacement (TAVR) for the treatment of AS-patients. TAVR induces an immediate decrease in hyperemic microcirculatory resistance and a concomitant increase in hyperemic flow velocity, whereas resting coronary hemodynamics remain unaltered. These findings suggest that FFR may underestimate coronary stenosis severity in AS-patients, whereas iFR as the non-hyperemic index is independent of the AS severity. However, because resting coronary hemodynamics do not improve immediately after TAVR, the coronary vasodilatory capacity in AS-patients treated by TAVR remain impaired, and thus the iFR may overestimate coronary stenosis severity in these patients. The optimal method for evaluating myocardial ischemia in patients with AS and co-existing CAD has not yet been fully established, and this important issue is under further investigation. This review is focused on challenges, limitations, and future perspectives in the functional assessment of coronary stenosis severity in these patients, bearing in mind the complexity of coronary physiology in the presence of this valvular heart disease.

Baseline, procedural and outcome features of patients undergoing transcatheter aortic valve implantation according to different body mass index categories

BACKGROUND

Transcatheter aortic valve implantation (TAVI) has become first-line treatment for severe aortic valve stenosis in patients with moderate, high or prohibitive surgical risk. However, access site complications may occur more frequently in extreme body mass index (BMI) categories. The aim of this study was to describe the features and outcomes of patients undergoing TAVI in a comprehensive Italian prospective clinical registry, focusing on BMI classes.

METHODS

A national prospective database was queried for baseline, procedural, and outcome details of patients undergoing TAVI according to established BMI categories: underweight (BMI <18.5 kg/m2), normal weight (BMI 18.5-24.9 kg/m2), overweight (BMI 25.0-29.9 kg/m2), and obese (BMI≥30 kg/m2). Short- and long-term outcomes, including major adverse events (MAE), i.e. the composite of death, stroke, myocardial infarction, major vascular complication, major bleeding, or renal failure, were appraised with bivariate and multivariable analyses.

RESULTS

A total of 3075 subjects were included, 64 (2.1%) were underweight, 1319 (42.9%) were normal weight, 1152 (37.4%) were overweight, and 540 (17.6%) were obese. Several baseline differences were evident, including gender, diabetes mellitus, renal function, chronic obstructive pulmonary disease, surgical scores, and left ventricular ejection fraction (LVEF) (all P<0.05). Several procedural differences were also evident, including percutaneous approach, predilation, prosthesis type and size (all P<0.05), with postprocedural aortic regurgitation >2+ significantly more common in underweight patients (P<0.05). Nonetheless, unadjusted analysis for one-month outcomes showed similar rates for fatal and non-fatal outcomes, including MAE (all P>0.05), with the notable exception of permanent pacemaker implantation, which was more common in higher BMI classes (P=0.010) Unadjusted analysis for long-term events showed an increased rate of death in underweight patients (P=0.024). Multivariable adjusted analysis confirmed the increased risk of permanent pacemaker implantation in obese patients (P=0.015 when comparing obese vs. normal weight subjects), but disproved differences in long-term mortality and other outcomes (P>0.05 for all comparisons).

CONCLUSIONS

Irrespective of BMI class, TAVI is associated with favorable outcomes in surgical high-risk risk patients, with the notable exclusion of permanent pacemaker implantation, which is significantly more common in obese subjects.