Changes in right ventricular two-dimensional echocardiographic speckle-tracking indices in adult LVAD population: a prospective clinical study

Objective

Preserved right ventricular (RV) function is crucial in patients supported with left ventricular assist devices (LVAD). The use of strain derived from speckle tracking echocardiography (STE) is recommended by recent guidelines to evaluate intricate RV contractility. The data regarding long-term RV observation in LVAD patients using STE are limited. Thus, the study aimed to determine RV systolic function by STE in the remote period after LVAD implantation.

Methods

Patients with implanted third-generation LVADs with hydrodynamic bearing were prospectively enrolled (NCT05063006). The RV STE indices were analyzed before and after LVAD implantation, both at rest and during the cycle ergometer exercise test.

Results

We included 22 patients, the mean age was 58.4±7 years, 95.5% were men, and 45.5% had dilated cardiomyopathy. Stress tests were conducted 7 months postoperatively. The RV strain analysis was feasible in all subjects both in rest and exercise. The RV free wall strain (RVFWS) worsened from −13% (IQR, −17.3 to −10.9) to −11.3% (IQR, −12.9 to −6; p=0.033) after LVAD implantation with the particular decline in the apical RV segment [−11.3% (IQR, −16.4 to −6.2) vs −7.8% (IQR, −11.7 to −3.9; p=0.012)]. The RV four-chamber longitudinal strain (RV4CSL) remained unchanged [−8.5% (IQR, −10.8 to −6.9) vs −7.3% (IQR, −9.8 to −4.7; p=0.184)]. Neither RVFWS (−11.3% (IQR, −12.9 to −6) vs −9.9% (IQR, −13.5 to −7.5; p=0.077) nor RV4CSL [−7.3% (IQR, −9.8 to −4.7) vs −7.9% (IQR, −9.8 to −6.3; p=0.548)] changed during cycle ergometer stress test.

Conclusion

The RVFWS worsens after LVAD implantation presumably due to impaired apical contractility. In LVAD-supported patients during the cycle ergometer stress test, the detailed RV strain analysis is feasible and its indices remain unchanged.

Funding Acknowledgement

Type of funding sources: Other. Main funding source(s): 1. Cor Aegrum Foundation of Cardiac Surgery Development in Cracow2. Medtronic Poland sp. z o.o.

Outcomes of COVID-19 patients with STEMI undergoing primary PCI

Introduction and aim

Coronavirus disease (COVID-19) has substantial impact on acute myocardial infarction (AMI) clinical course and outcome.

In Poland during early phase of COVID-19 pandemic a network of dedicated hospitals was set to treat SARS-Cov2 positive patients. There is scarce data on STEMI patients outcome treated in this setting.

Our aim was to compare outcomes of STEMI patients treated with primary PCI in hospitals dedicated to treat COVID-19 and referral high volume haemodynamic centres.

Methods

Study was a retrospective analysis of 115 consecutive COVID-19 patients with STEMI, treated with primary PCI, admitted to 4 high volume centres (2 referral hospitals and 2 COVID dedicated sites) in southern Poland between May 2020 and November 2021. Data was obtained from patients' electronic medical records.

Results

Detailed characteristics are presented in Table 1 and 2. In general in all hospitals, patients were similar in terms of age (median 69 y.o., IQR: 60–73), with similar profile of comorbidities. All patients used acetylsalicylic acid and unfractioned heparin.

In referral centres, as compared with COVID-19 dedicated sites, there was a higher use of mechanical thrombectomy (p<0.001) and adenosine (p<0.001). Overall mortality rate was higher in COVID-19 centres (50% vs 25%, p=0.008). Detailed results are presented in Table 3.

Conclusions

There is a significantly higher mortality in COVID patients who develop STEMI than in patients with STEMI who were tested positive on admission.

Patients in COVID-19 hospitals had higher levels of CRP and NT-proBNP at baseline.

There are substantial differences in treatment of patients in referral centres and COVID dedicated hospitals.

Funding Acknowledgement

Type of funding sources: None.

Heterogeneous and overlapping mechanisms of myocardial ischemia in patients with ischemia and non-obstructive coronary arteries. Preliminary results from the MOSAIC-COR Registry

Background

Patients with ischemia and non-obstructive coronary arteries (INOCA) account for 30–70% of all patients undergoing elective coronary angiography for angina. In these group of patients various mechanisms may be responsible for myocardial ischemia, including increased microvascular resistance, epicardial spasm or microvascular spasm. There are limited data on the prevalence and coexistence of different mechanisms in patients with INOCA.

Purpose

The primary objective was to assess the occurrence of coronary microcirculatory disease (CMD), epicardial vasospastic angina (EVSA), microvascular vasospastic angina (MVSA) and their coexistance in patients with INOCA. The secondary objective was the analysis of subgroups' clinical characteristics.

Methods

This was a single-center, prospective, observational study. In the absence of significant coronary artery stenosis, a complex functional coronary assessment was performed. Values of fractional flow reserve (FFR), RFR, coronary flow reserve (CFR) and index of microcirculatory resistance (IMR) were determined. Coronary artery and microvascular vasoreactivity was tested using the provocative acetylcholine test.

Results

We enrolled 90 consecutive patients with INOCA. Overlapping of CMD and CMD/EVSA phenomenon was observed. Accordingly, we distinguished 6 subgroups of INOCA patients in comparison to the CorMicA trial. Mixed pathophysiology (CMD+EVSA and CMD+MVSA) was diagnosed in 33% of patients. In the CMD+EVSA subgroup, 73% of subjects were male, while in the CMD+MVSA only 7.1% were male (p=0.005). Typical cardiovascular risk factors were common in the whole INOCA group.

Conclusions

The INOCA population is a heterogeneous group with various pathophysiology of myocardial ischemia. Overlapping of different pathomechanisms is a frequent phenomenon, which has to be consider for treatment optimization and future research.

Funding Acknowledgement

Type of funding sources: None.

Echo-guided LVAD speed optimization for exercise maximization

Background

Continuous-flow left ventricular assist devices (LVAD) are becoming a destination therapy in patients with end-stage left ventricular dysfunction and a competitive method for heart transplantation. Current generation pumps operate with a fixed rotation speed and do not have the automatic speed adjustment capability. However, it was shown that acceleration of the pump speed during stress test increases the maximum exercise tolerance.

Purpose

The study aimed to evaluate the concept of dynamic pump speed optimization based on the echocardiographic assessment of aortic valve opening (AVO) during the cardiopulmonary exercise test (CPET).

Methods

Patients with implanted third-generation centrifugal continuous-flow LVAD's with hydrodynamic bearing were prospectively included. Two CPET's were performed after resting speed optimization. The first one with maintained baseline pump speed settings, and the second one with gradually increased speed depending on live echocardiographic imaging. The sequence of tests was random.

Results

Exercise AVO was apparent in all 22 included patients. The resting pump speed was 2691 RPM and incremented on average by 566 RPM (20%). Pump power and flow raised from 5.6 to 9.8 Watts (p<0.0001) and from 5.8 to 7.3 l/min (p<0.0001), respectively. Peak VO2 increased from 11.1 to 12.8 ml/kg/min (p=0.0003) and maximum workload from 1.1 to 1.2 W/kg (p=0.03). The Borg scale exertion level decreased from 15.2 to 13.5 (p=0.0049). There was a visible trend towards longer exercise time (36s) but no statistical significance was achieved (p=0.1).

Conclusion

Ultrasonographic AVO analysis is possible during CPET's in patients supported with LVAD. Dynamic echo-guided pump speed adjustment based on the AVO improves exercise tolerance, augments peak VO2 consumption and maximal workload. An automatic speed adjustment in the next generations of LVAD controllers might improve functional capacity and requires further basic, technological and clinical research.

Funding Acknowledgement

Type of funding sources: Other. Main funding source(s): 1. Cor Aegrum Foundation of Cardiac Surgery Development in Cracow2. Medtronic Poland Sp. z o.o.

Comparison of iFR and FFR for coronary physiology evaluation in patients with severe aortic stenosis

Background

Reliable coronary physiology assessment with pressure derived indexes in patients with aortic stenosis (AS) rises problems due to its complex nature. Recent data suggest that fractional flow reserve (FFR) may underestimate intermediate coronary stenosis in a presence of AS whereas instantaneous wave-free ratio (iFR) values may remain similar after treatment of AS. Furthermore, both indices has not been validated yet in AS.

Aim

We aimed to find a thresholds for coronary ischemia in the setting of aortic

Material and methods

The functional significance of 416 coronary lesions was investigated with iFR and FFR measurements in 221 AS patients. The iFR-FFR diagnostic agreement has been tested using the cut-off value for iFR of 0.89.

Results

Mean value of %DS was 58.6±13.4%, FFR was 0.85±0.07 and iFR – 0.90±0.04. FFR ≤0.80 was measured in 26.0% of interrogated vessels, iFR ≤0.89 – in 33.2%. The correlation between iFR and FFR was good (r=0.83, p<0.001) and with good agreement between iFR and FFR (mean difference −0.0059, 95% CI −0.056–0.062). The AUC at ROC curve analysis for iFR ≤0.89 was 0,997 (0,986 to 1,000, p<0.001) for FFR. According to ROC analysis, the best FFR cut-off in predicting iFR ≤0.89 was ≤0.82 (J=0.96). The diagnostic accuracy for identifying iFR ≤0.89 was 97.7% for FFR.

Conclusion

In the presence of AS, FFR had good agreement with iFR values. However, FFR threshold for predicting iFR below 0.89 may be different from a standard threshold and that should be taken into account while assessing coronary physiology in the setting of AS.

Funding Acknowledgement

Type of funding source: Public grant(s) – National budget only. Main funding source(s): National Science Center

Comparison of FFR with iFR and QFR in assessment of intermediate coronary artery disease in patients with severe aortic stenosis

Background

The functional assessment of coronary artery disease (CAD) in patients with severe aortic stenosis (AS) has been barely examined so far, and the best strategy to physiologically investigate the relevance of coronary stenosis in this specific setting of patients remains undetermined. The aim of the study is to compare the diagnostic performance of instantaneous wave-free ratio (iFR), quantitative flow ratio (QFR) and fractional flow reserve (FFR) in patients with severe AS.

Methods

The functional significance of 416 coronary lesions was investigated with iFR, FFR and QFR measurements in 221 AS patients. The iFR-FFR and QFR-FFR diagnostic agreement has been tested using the conventional 0.80 FFR cut-off.

Results

Mean value of FFR was 0.85±0.07; iFR – 0.90±0.04; QFR – 0.84±0.07. The correlation between iFR and FFR was good (r=0.83, p<0.001) and QFR and FFR was goot too (r=0.77, p<0.001), as well as the area under the curve at ROC curve analysis 0,995 (0,983 to 0,999, p<0.001) for iFR and 0,988 (0,972 to 0,996, p<0.001) for QFR. However, using the standard iFR 0.89 and QFR 0.8 threshold, the diagnostic accuracy of iFR was 100% sensitivity and 90.26% specificity and for QFR – 100% and 92.21%, respectively. According to ROC analysis, the best iFR cut-off in predicting FFR ≤0.8 was 0.88 (J=0.94), the best QFR cut-off value was 0.80 (J=0.92).

Conclusions

In the presence of severe AS, iFR and QFR had good agreement with FFR values for assessment of borderline coronary lesions. However, iFR threshold for predicting FFR below 0.8 may be different from a standard value of 0.89.

Funding Acknowledgement

Type of funding source: Public grant(s) – National budget only. Main funding source(s): National Science Centre

Correlations between fractional flow reserve and a novel non-hyperemic index: resting full-cycle ratio in patients with an ambiguous coronary artery stenosis

Background

Fractional flow reserve (FFR) measurement has been the gold standard for invasive assessment of coronary ischemia. Resting full cycle ratio (RFR) is a new non-hyperemic index used to define physiologic significance of coronary artery stenosis. However, there are limited data available to establish optimal cut-off value of RFR for decision making on revascularization.

Aim

The aim of our study was to assess optimal cut-off value of RFR at which to predict FFR of 0.8.

Methods

The RFR and FFR values were recorded during invasive coronary angiography in vessels with angiographic stenosis 40–70% according to visual assessment. Maximum hyperemia for FFR measurement was achieved with adenosine iv. infusion at 140 μg/kg/min. Left main disease, acute myocardial infarction and systolic left ventricular dysfunction (EF <40%) were the main exclusion criteria.

Results

We evaluated 332 vessels, including 189 (56.9%) left anterior descending arteries, 77 (23.2%) left circumflex arteries and 66 (19.9%) right coronary arteries. Median diameter stenosis as assed by QCA was 45% (IQR 40; 50). Median RFR and FFR values were 0.90 [IQR 0.85; 0.94] and 0.86 [IQR 0.81; 0.92] respectively, with significant correlation (p<0.001, Figure 1, panel A). Optimal cut-off value for RFR to detect FFR 0.80 was 0.90 with area under the curve of 90.3%, sensitivity of 81.4% and specificity 88.0% (Figure 1, panel B).

Conclusions

Our data confirm RFR cut-off value ≤0.90 as an optimal threshold to detect ischemic lesions with good sensitivity and specificity in comparison to FFR assessment. Further research is necessary to assess outcomes of RFR-guided revascularization strategy.

Figure 1. RFR–FFR correlation and ROC analysis

Funding Acknowledgement

Type of funding source: Other. Main funding source(s): Jagiellonian University statutory grant

P4706Sex-related differences in clinical outcomes after percutaneous transluminal angioplasty in patients with peripheral artery disease

Aim

There are inconsistent data on the sex-related differences in clinical outcomes after percutaneous transluminal angioplasty (PTA) in patients with peripheral artery disease (PAD). We aimed to investigate sex-related differences in clinical outcomes after PTA.

Methods

A total of 939 consecutive patients undergoing PTA were enrolled in two large volume centers. Patients were stratified by gender. Baseline characteristics, procedural and long-term clinical outcomes were compared between women and men.

Results

Women represented 37.4% of the study population. Women, compared to men, had more often hypertension (92% vs 86%, p=0.001) and diabetes (54% vs 46%, p=0.02). However, men presented more often with chronic obstructive pulmonary disease (14.8% vs 6.8%, p=0.0003), coronary artery disease (45.4% vs 32.7%, p=0.0001), smoking (60.4% vs 45%, p=0.007) and previous PTA (25% vs 17%, p=0.005). There were no differences in 120-month all-cause mortality between groups (women vs. men: 29% vs. 21%, p=0.6). Men were at higher risk of re-PTA at 5-year follow-up (40% vs. 49%; p=0.03). Moreover, male sex was an independent predictor of re-PTA (age-adjusted odds ratio (OR) (95% CI): 1.276 (1.015–1.614), p=0.03). In multivariable Cox regression analysis, a superficial femoral artery chronic total occlusion (SFA-CTO) (hazard ratio [HR]) (95% confidence interval [CI]): 1.68 (1.12–2.5), body mass index (BMI) (hazard ratio (HR)) (95% CI): 0.93 (0.87–0.99), baseline creatinine level hazard ratio (HR)) (95% CI): 0.95 (0.88–0.99) were identified as independent factors of re-PTA in women.

Figure 1. Months to re-PTA for grouping variable male.

Conclusion

Male sex was identified as an independent predictor of re-PTA. SFA-CTO, BMI and baseline creatinine level were associated with re-PTA in women.