P295 EXERCISE OXYGEN KINETIC IN HYPERTROPHIC CARDIOMYOPATHY: RESULTS FROM A MULTICENTER CARDIOPULMONARY EXERCISE TESTING STUDY

Aims

Reduced cardiac output (CO) has been considered crucial in symptoms’ genesis in hypertrophic cardiomyopathy (HCM). We evaluated the cardiopulmonary exercise testing (CPET) response in HCM focusing on parameters strongly associated with stroke volume (SV) and cardiac output (CO), such as oxygen uptake (VO2) and O2–pulse, considering both their absolute values and temporal behavior during physical exercise.

Methods and Results

We enrolled 312 non–end stage HCM patients, divided according to left ventricle outflow tract obstruction (LVOTO) at rest or during Valsalva maneuver (72% with LVOTO<30; 10% between 30 and 49 and 18% ≥ 50mmHg). Peak VO2 (percent of predicted), O2–pulse and ventilation to carbon dioxide production (VE/VCO2) slope did not change across LVOTO groups. Ninety–six (31%) HCM patients presented an abnormal O2–pulse temporal behavior, irrespective of LVOTO values. These patients showed lower peak systolic pressure, workload (106±45 vs. 130±49W), VO2 (74±17 vs. 80±20%) and O2–pulse (12 [9–14] vs. 14 [11–17]ml/beat), with higher VE/VCO2 slope (28 [25–31] vs. 27 [24–31]) (p < 0.005 for all). Only 2 patients had an abnormal VO2/work slope.

Conclusion

None of CPET parameters, either as absolute values or dynamic relationships, were associated with LVOTO. Differently, an abnormal O2–pulse exercise behavior, which is strongly related to inadequate SV during exercise, correlates with reduced functional capacity (peak and anaerobic threshold VO2 and workload) and increased VE/VCO2 slope, helping identifying more advanced disease irrespectively of LVOTO. Adding O2–pulse kinetics evaluation to standard CPET could lead to a potential incremental benefit in terms of HCM prognostic stratification and, then, therapeutic management.

P244 BRISK WALKING CAN BE A MAXIMAL EFFORT IN HEART FAILURE PATIENTS. A COMPARISON OF CARDIOPULMONARY EXERCISE AND SIX–MINUTE WALKING TEST CARDIORESPIRATORY DATA

Aims

Cardiopulmonary exercise test (CPET) and six–minute walking test (6MWT) are frequently used in heart failure (HF). CPET is a maximal exercise, whereas 6MWT is a self–selected constant load test usually considered a submaximal, and therefore safer, exercise but this has not been tested previously. The aim of this study was to compare the cardiorespiratory parameters collected during CPET and 6MWT in a large group of healthy subjects and patients with HF of different severity.

Methods and Results

Subjects performed a standard maximal CPET and a 6MWT wearing a portable device allowing breath–by–breath measurement of cardiorespiratory parameters. HF Patients were grouped according to their CPET peak oxygen uptake (peakV̇O2). One–hundred and fifty–five subjects were enrolled, of whom 40 were healthy (59±8 years; male 67%) and 115 were HF patients (69±10 years; male 80%; left ventricular ejection fraction 34.6±12.0%). CPET peakV̇O2 was 13.5±3.5 ml/kg/min in HF patients and 28.1±7.4 ml/kg/min in healthy (p < 0.001). 6MWT–V̇O2 was 98±20% of the CPET peakV̇O2 values in HF patients, while 72±20% in healthy subjects (p < 0.001). 6MWT–V̇O2 was >110% of CPET peakV̇O2 in 42% of more severe HF patients (peakV̇O2<12ml/kg/min). Similar results have been found for ventilation and heart rate. Of note, the slope of the relationship between V̇O2 at 6MWT, reported as percentage of CPET peakV̇O2 vs. 6MWT V̇O2 reported as absolute value, progressively increased as exercise limitation did.

Conclusions

6MWT must be perceived as a maximal or even supra–maximal exercise activity at least in patients with severe exercise limitation from HF. Our findings should influence the safety procedures needed for the 6MWT in HF.

Cardiac reverse remodelling by 2D and 3D echocardiography in heart failure patients treated with sacubitril/valsartan: a prospective study

Background

Left ventricular (LV) reverse remodelling induced by sacubitril/valsartan (S/V) has been shown in heart failure patients with reduced ejection fraction (HFrEF) by two-dimensional (2D) transthoracic echocardiography (TTE). Data about S/V effect on the right ventricle (RV) are scarce.

Aims

We aimed to evaluate S/V-induced changes in NT-proBNP levels, and cardiac remodelling indices by 2D and three-dimensional (3D) TTE in HFrEF patients, classifying patients according to aetiology.

Methods

We prospectively enrolled 51 HFrEF patients (24 ischaemic, 27 non-ischaemic). At baseline and at 6-months follow-up (6MFU) after S/V treatment optimization, we i) assessed NT-proBNP; ii) performed 2D TTE according to guidelines for the assessment of biventricular size and function, mitral regurgitation grade and LV diastolic function; and iii) performed 3D TTE, using the Dynamic HeartModel software for the evaluation of LV volumes and function, the 4D LV-Analysis software for the assessment of LV longitudinal strain, and the 4D RV-Analysis software for the assessment of RV volumes and function (Figure 1).

Results

In non-ischaemic patients, both 2D and 3D TTE showed an improvement in LV volumes and biventricular function, whereas only 3D detected a reduction in RV size at 6MFU vs baseline (Table 1). In ischaemic patients, only 3D TTE showed an improvement in biventricular size and LV function (Table 1). Finally, S/V induced a significant improvement in NT-proBNP (Table 1) and diastolic function both in ischaemic and non-ischaemic groups: patients with elevated left atrial pressure (as assessed by 2D parameters of diastolic function) decreased from 45% to 20% in ischaemic and from 40% to 10% in non-ischaemic patients (p<0.05).

Conclusions

S/V induced a significant improvement in NTproBNP and diastolic function in both aetiologic groups. A clinically significant improvement in biventricular function was shown only in non-ischaemic patients. 3D TTE may be advantageous to ascertain subtle changes in LV size and function, undetected by 2D imaging, and to evaluate RV dimensions and function, which have a major impact on HFrEF prognosis.

Funding Acknowledgement

Type of funding sources: None. Figure 1Table 1

P638 Short term reverse remodeling and exercise capacity improvement in a patient with valvular heart failure treated with Sacubitril Valsartan

Background

Sacubitril/valsartan is a first-in-class angiotensin receptor-neprilysin inhibitor (ARNI) recommended in the guidelines to reduce morbidity and mortality in patients with symptomatic heart failure (HF) with reduced ejection fraction (HFrEF). Although the recent widespread use of the drug, data on left ventricle (LV) reverse remodeling and improvement in functional capacity (FC) under treatment are still lacking.

Case presentation

A 73 years old man with a known HFrEF was admitted to the hospital for clinical review due to progressive worsening dyspnea in the last 6 months (NYHA class III) with high NTproBNP values. Echocardiography showed dilated LV (EDVi/ESVi 137/98 ml/m2) with severe reduction in ejection fraction (EF), moderate/severe aortic incompetence, moderate functional mitral regurgitation. A maximal, ramp-protocol, cardiopulmonary exercise test (CPET) showed a moderate reduction in FC with signs of cardiogenic limitation. He was started on Sacubitril/Valsartan 24/26mg b.i.d. with progressive up-titration of the dose until a maximum dose of 97/103mg b.i.d. and without any other change in the therapy. ARNI was well tolerated without hypotension, worsening renal function or hyperkaliemia. After 3 months the echocardiography showed a reduction in LV volumes (EDVi/ESVi 112/72 ml/m2) with mild improvement in EF (from 28% to 34%) and increased FC, leading to a 56% reduction in estimated HF mortality at 2 years assessed through MECKI Score (See tab. 1 and Fig. 1). NTproBNP value was also reduced compared to baseline.

Conclusion

We present a case of a short term improvement in LV and atrium volumes and FC after 3 months of treatment with Sacubitril/valsartan in a patient with HFrEF. More studies are needed to assess LV volumes and CPET values response to ARNI.

Tab.1 Basaline 3 months Δ NYHA Class II III - MECKI Score (%) 5.12 2.23 -56-4% Peak VO2 /% of predicted) 60 72 +20% Maximal Work (W) 68 83 +22.1% Mitral regurgitation ++ + - eGFR (ml/min/1,73m2) 64 65 +1.6% Potassium (mmol/L) 4.26 4.20 -1.4% Aortic regurgitation +++ ++ - Clinical changes after the 3 months follow-up

Abstract P638 Figure. Fig. 1

410 Early cardiac reverse remodeling in a large cohort of patients with HFrEF treated with Sacubitril/Valsartan

Background

Despite the widespread use of Sacubitril/valsartan (Sac/Val) in patients with reduced ejection fraction (HFrEF), definite data on cardiac remodeling under treatment are still lacking.

Methods

We conducted a retrospective analysis on a large cohort of 201 consecutive HFrEF ambulatory patients who started Sac/Val in our HF unit between Sept. 2016 and Dec. 2018 on top of optimal medical treatment. Patients with both basal and follow up (at least 3 months) echocardiographic assessment (TTE) were included.

Results

A follow up TTE was performed in 100 patients (male 76%; mean age 67.4 ± 11.1 years; medium follow-up 309 ± 182 days). Baseline characteristics are shown in Tab.1. 34% of the patients reached the maximal dose (97/103 b.i.d.) while 18 interrupted the treatment. We observed an overall significant improvement in ejection fraction (EF), end-diastolic and end-systolic ventricular volumes (EDV/ESV), while just a trend in pulmonary pressures (PAPs) and mitral regurgitation (MR) reduction was noted (p = 0.06 and 0.09 respectively). Non ischemic etiology and high dose of Sac/Val were predictors of better remodeling (Fig.1).

Conclusion

In our study Sac/Val led to an early favorable ventricular remodeling assessed by echocardiography. The observed benefit was greater in patients on higher dose of the drug and non ischemic etiology.

Table 1 n = 100 Clinical characteristics Systolic blood pressure (mmHg) 116 ± 11 Diastolic blood pressure (mmHg) 70 ± 9 Hemoglobin (g/dL) 13 ± 2.0 MDRD (ml/min/1.73 m2) 63 ± 21.4 Potassium (mmol/L) 4.26 ± 0.50 NYHA class II (n;%) 59 (59%) NYHA class III (n;%) 41 (41%) Ischemic etiology (n;%) 58 (58%) ICD (n;%) 41 (41%) CRT (n;%) 32 (32%) Beta-blockers (n;%) 94 (94%) ACEi or ARBs (n;%) 92 (92%) MRA (n;%) 77 (77%) Baseline clinical characteristics

Abstract 410 Figure. Fig. 1

Prognostic factors in Merkel cell carcinoma patients undergoing sentinel node biopsy

INTRODUCTION

Debate remains about prognostic factors in primary Merkel cell carcinoma (MCC). We investigated clinicopathological factors as determinants of survival in patients with MCC submitted to sentinel node biopsy.

METHODS

Sixty-four consecutive patients treated for a primary MCC were identified from a prospectively maintained database at Fondazione IRCCS Istituto Nazionale dei Tumori, Milan. Time to events outcome were described by product limit estimators and proportional hazards model was used to investigate the association between outcome and potential predictors.

RESULTS

The most common site of primary tumor was lower limbs (56.3%). The size of primary lesion was ≤2 cm in 67.2% of cases. Presence of residual disease after the diagnostic surgical excision was observed in 28% of cases. All patients received sentinel node biopsy (SNB) and a SN positivity was detected in 26.6%. The median follow up was 78 months. Disease recurrence occurred in 17 patients (26.6%). In the SN negative group 10 recurrences occurred (21.3%), whereas 7 (41.2%) were found in SN positive one. Nine patients SN negative (19.1%) died of disease and 3 (17.6%) among SN positive. SN status was not associated with survival (p = 0.78). Neither age, gender, size and site of primary tumor resulted predictors of patients' outcome. The presence of residual tumor in the specimen of the wide local excision, after the diagnostic surgical excision, was the only variable associated with survival (p = 0.03).

CONCLUSIONS

Presence of residual tumor in the specimen of the wide local excision is the main prognostic factor in MCC patients.