Global longitudinal strain for prediction of mortality in ST-segment elevation myocardial infarction and aortic stenosis patients: two sides of the same coin

OBJECTIVE

Global longitudinal strain (GLS) predicts major adverse events in ST-segment elevation myocardial infarction (STEMI) and aortic stenosis (AS). Different cut-off values and different end-points have been proposed for prognostic stratification. We aimed to verify whether a single GLS cut-off value can be used to identify increased risk of all-cause death in STEMI and AS.

PATIENTS AND METHODS

One-hundred- seventeen successfully treated first STEMI (age 63.8±12.5 yrs, 70% men) and 64 AS (age 80.3±6.9 yrs, 44% men) patients, undergoing echocardiography before discharge and before AS treatment, respectively, were retrospectively analyzed. GLS was analyzed, together with pulmonary artery systolic pressure (PASP), Killip class and Genereux stage. End-point was all-cause death at 6-month follow-up.

RESULTS

All-cause death occurred in 4 (3.4%) STEMI and 5 (7.8%) AS patients (p=ns). AS patients who died had GLS similar to died STEMI patients (9.7±2.1 vs. 11.3±1.7, p=ns). GLS cut-off ≤12% predicted death with 89% sensitivity and 70% specificity (AUC 0.84, p=0.001): STEMI and AS patients with GLS ≤12% had worse survival than STEMI and AS patients with GLS >12% (log-rank p=0.001). At multivariate Cox regression analysis, lower GLS values independently predicted death (HR 0.667, 95% CI 0.451-0.986, p=0.042), and the prediction model was improved when GLS was added to old age, significant comorbidities, PASP and Killip/Genereux stage (χ2 6.691 vs. 1.364, p=0.010).

CONCLUSIONS

Died patients with STEMI and AS show similar values of GLS. A unique cut-off value of GLS can reliably be used to stratify the risk of all-cause death at 6-month follow-up in both two clinical settings.

P734 Feasibility and accuracy of the new automated software dynamic heart model in an unselected population

Objective

Preliminary studies showed the accuracy of machine learning based automated dynamic quantification of left ventricular (LV) and left atrial (LA) volumes. We aimed to evaluate the feasibility and accuracy of this new Dynamic Heart Model (DHM) software in an unselected population undergoing transthoracic echocardiography (TTE). Methods. We enrolled 91 consecutive unselected patients (80% in sinus rhythm) referred for clinically indicated 2D TTE, who also underwent single 3D TTE image acquisition from the apical 4-chamber view. 2D images were analyzed to measure ejection fraction, LV and LA volumes; 3D images were analyzed using Dynamic Heart Model (DHM) software (Philips Healthcare), which automatically measures chamber volumes throughout the cardiac cycle, resulting in LV and LA volume-time curves. Average time of analysis, feasibility, image quality were recorded and results compared between the 2D and 3D techniques. Results. Quality of the 91 2D TTE images was graded as poor (N = 13), satisfactory (N = 45) and good (N = 33). The use of DHM was feasible in 79/91 cases (87%). The remaining 12 datasets could not be analyzed because of poor images (N = 10) or incorrect automated border detection (N = 2): in these cases, the software did not accurately identify endocardial borders due to LV cavity near obliteration or extreme LA enlargement. When feasible, the boundary position was considered accurate in 61/79 patients (77%), while minor manual correction of the LV/LA borders was needed in the remaining cases. In only 1 case the reconstruction was considered unreliable because it needed major corrections. The overall time required to obtain DHM data was approximately 45 seconds. In all cases in which DHM was used, not only shapes of LV and LA were very well defined, but also functional curves were physiologically plausible. Even in the 13 patients in whom the 2D image was suboptimal, the DHM was not only feasible but also accurate endocardial boundaries in 8 cases, without (N = 5) or with only minimal manual corrections (N = 3). As expected, 3D LV volumes were slightly hige than 2D ones ( EDV 153.9 ± 59.8 vs 121.4 ± 47.3 mL, respectively), while LV EF and LA volumes were similar (EF 58.8 ± 11.8 vs 59 ± 11.8% and LA volume 92 ± 39.3 vs 83.4 ± 32.1 mL, respectively). Conclusions. The new DHM software is quick, feasible and accurate in the majority of unselected patients, including those with suboptimal 2D images or in atrial fibrillation. Introduction of this automated analysis into clinical practice can reduce examination time, while providing reliable information not only on volumes but also on function of the left heart chambers.

P1424 Long-term follow-up in patients undergoing early surgery (repair) for severe degenerative mitral regurgitation

In conclusions

a) early MV repair is associated with favourable LV remodelling and stable systolic function at FU; b) 2DTTE predicts in an early surgical strategy favourable LV remodelling c) pre-operative 3DTTE morphology (simple vs complex MVP) predicts repair procedure (simple vs complex) that in the large majority (91%) is associated with freedom from MR recurrence.

Table Pre-op 6-month FU 3-years FU Left ventricular end diastolic volume (ml) 140 ± 41 104 ± 30 * 103 ± 35 Left ventricular end systolic volume (ml) 49 ± 19 45 ± 19* 43 ± 22 Left ventricular ejection fraction (%) 65 ± 7 58 ± 8* 59 ± 7§ Mitral regurgitation (+) 3.9 ± 0.2 0.6±.6* 0.9±.9§ Left atrial volume (ml) 123 ± 48 91 ± 35* 87 ± 45 *= p < 0.01 6 ms vs pre-op; §=p < 0.01 3ys vs 6 ms

P1522 Long term follow-up after early mitral valve surgery. Role of 3D echocardiographic right chambers evaluation in predicting tricuspid regurgitation development

Background

Combined mitral and tricuspid surgery is recommended in patients diagnosed with significant tricuspid regurgitation (TR) or dilatation of tricuspid annulus (TA) undergoing mitral valve (MV) surgery. Despite the prognostic value of significant TR is well known, the role of TA is still debated, due to inaccuracy of 2D measurements. Data about the role of 3D echocardiographic evaluation of TA and right chambers in predicting TR development after early MV surgery are lacking.

Purpose

To test whether a comprehensive 3D evaluation of right chambers and TA may predict TR development after early surgery in patients with MV prolapse, at a long term follow-up.

Methods

Between 2012 and 2015, 100 patients diagnosed with MV prolapse and severe mitral regurgitation, who underwent early MV repair were retrospectively studied. All patients underwent 3D transthoracic examination before surgery; for each patient right atrial (RA) volume and right ventricular (RV) volumes, function and strain were derived. 3D dimensions and function of TA were also measured using commercial software. The median follow-up was 48 months.

Results

9 patients underwent TVR for moderate TR and were excluded. At baseline, our patients showed more than moderate TR, normal 3D RV volumes and function (EDV 67 ±16ml/m2, EF 56 ± 6%, GLS free wall 28 ± 5 %) and RA volume (54 ± 15 ml/m2). Pulmonary artery pressure was 36 ±9 mmHg. Based on 2D evaluation, dilatation of TA (more than 21 mm/m2) was measured in 21 patients over 91. 3D analysis of TA showed a function of 38 ± 12% and a major axis of 46 ± 6 mm no significant differences in 3D values were noted between patients with normal and dilated annuli. Based on 2D. Over the follow-up, none of our patients developed clinically significant TR (more than moderate)

Conclusion

Patients who underwent early MV repair with normal 3D values of right chambers have a low risk of developing TR, regardless of 2D dimensions of TA.

P332 is 3D analysis of longitudinal strain useful to predict cardiac events in patients undergoing mitral valve repair?

Background

The presence of abnormal 3D left ventricular (LV) strain values in patients diagnosed with mitral valve prolapse (MVP) and significant mitral regurgitation (MR) has been described previously. Recently, some studies showed an addictive prognostic role of Global Longitudinal Strain (GLS) in patients with severe aortic regurgitation. Few data are available about the prognostic role of LV strain in patients diagnosed with severe MR secondary to Myxomatous or fibroelastic deficiency (FED) MVP, undergoing MV repair.

Purpose

The aim of the study was to determinate whether LV GLS, strain rate, twist rate and left atrial strain (LAS) may identify a subgroup of patients with MVP and severe MR at higher risk of clinical events after surgical repair in both Myxomatous and FED disease.

Methods

We retrospectively studied 100 patients diagnosed with MVP and severe MR due to Myxomatous or FED disease, eligible for MV surgery between 2012 and 2015. Only patients with normal LV function who underwent a 3D transthoracic echocardiographic examination were included. 3D LV GLS, strain rate, twist rate and LAS were measured using 3D analysis software. Clinical data were recorded during a median follow-up of 48 months. Clinical events included cardiac death, arrhythmia and cardiac hospitalization for heart failure or arrhythmic events.

Results

65 patients were diagnosed with Myxomatous and 35 with FED disease. A total of 13 events were recorded during the follow-up, including 1 death, 2 hospitalizations for heart failure and 10 minor arrhythmic events, mostly isolated premature ventricular complex. The number of events was not statistically different between the two groups. In both groups no significant correlation was found between clinical events and each of the echocardiographic parameters measured.

Conclusion

In patients with MVP and severe MR but normal LV function, undergoing MV repair, LV strain analysis was not able to predict long term cardiac events., regardless of the etiology.

P1590 Regional differences in longitudinal strain and response to adenosine stress in patients with myocardial infarction and ST-segment elevation. Results from Extreme trial

Background

Global longitudinal strain (LS) is a sensitive marker of ischemic myocardial damage and predicts adverse left ventricular (LV) remodeling and outcome, independently of infarct size. In healthy subjects, regional LS increases from LV base to apex and enhances under physical or pharmacological stress, while in ST-elevation myocardial infarction (STEMI), response to dobutamine depends on transmurality of necrosis. It is known that coronary flow reserve during adenosine (ADN) is impaired both in ischemic and remote myocardium, but effect of ADN on strain reserve has never been investigated. Similarly, LS response to ADN in ischemic (iLS) and remote (rLS) myocardium and their relative contribution to LV function and remodeling are still unknown.

Methods

61 consecutive patients with first STEMI (26 anterior, 29 inferior, 6 lateral), treated by successful primary percutaneous coronary intervention (PCI) followed by PCI of non-culprit coronary arteries, underwent rest and stress ADN (140 mcg/kg/minutes in 90 seconds) echocardiography at discharge (7 ± 2 days after admission). LV end-diastolic volume indexed for body surface area (EDV), ejection fraction (EF) and wall motion score index (WMSI) were measured at rest, while GLS, iLS and rLS analysis was performed both at rest and during stress. Ischemic and remote myocardium was allocated, by standard LV segmentation, basing on the culprit coronary artery.

Results

Significant differences existed among anterior, inferior and lateral STEMI in median (iQr) EDV [52 (45-59) vs 45 (36-51) vs 48 (45–56) ml, respectively, p=.034 overall], EF [47 (37-58) vs 58 (53–61) vs 56 (46-60)%, respectively, p=.002 overall], WMSI [1.63 (1.38–2) vs 1.25 (1.19-1.47) vs 1.41 (1.30-1.75), respectively, p=.001 overall]. GLS differed among anterior, inferior and lateral STEMI both at rest [13.75 (11.63-16.1) vs 19.5 (17.15-22.4) vs 17.85 (17.02-19), respectively, p<.001 overall] and during ADN [14 (12.35-16.15) vs 19.5 (17.9–22.05) vs 15.95 (14.40-19.48), respectively, p<.001], but did not change within groups. No differences were found between rest and stress iLS in any group. Similarly, rLS remained unchanged in anterior and inferior STEMI, and impaired after ADN in lateral STEMI [15.90 (11.45-18) at stress vs 16.8 (15.25-19.2) at rest, p=.043]. Inferior STEMI showed better iLS than anterior STEMI both at rest [17 (15.1–19.9) vs 13.75 (11.46-16.92), respectively, p=.001] and during stress [16.2 (15–20.4) vs 14.42 (12.67-15.83), respectively, p=.001].

Conclusions

In the subacute phase of STEMI, GLS, iLS and rLS are heterogeneous and depend on infarct site. After ADN, there is no strain reserve in ischemic neither in remote myocardium. This may reflect regional differences in the response of microcirculation and myocardium to ischemia or may underlie pre-existing pathophysiological differences in the coronary circulation

Microvascular ischemia in patients with successful percutaneous coronary intervention: effects of ranolazine and isosorbide-5-mononitrate

OBJECTIVE

About one-third of patients undergoing percutaneous coronary interventions (PCIs) for flow-limiting coronary stenosis continue to develop signs of myocardial ischemia (MI) during exercise stress test [EST], despite successful coronary revascularization. Coronary microvascular dysfunction is a likely major cause of the persistence of EST-induced MI in these patients.

PATIENTS AND METHODS

We studied 15 patients (14 men, age 67±5 years) fulfilling the following strict inclusion criteria: (1) recent PCI (<6 months), with drug-eluting stent, of coronary artery stenoses for stable angina, with evidence of full success (no residual stenosis >20% in any vessel); (2) persistence of ST-segment depression induction during EST. After a basal investigation, patients received either ranolazine (375 mg bid) or isosorbide-5-mononitrate (ISMN, 20 mg bid) for 3 weeks in a single-blind, randomized crossover study. Clinical assessment, symptom-limited EST, echocardiographic color-Doppler, with tissue-Doppler examination, and coronary microvascular dilator response to adenosine (CFR-ADO) and cold pressor test (CFR-CPT), assessed by transthoracic echo-Doppler, were obtained at baseline and the end of the 3-week therapy with each drug.

RESULTS

Compared to both baseline and ISMN, ranolazine showed a longer time to 1 mm ST-segment depression (404±116 s vs. 317±98 and 322±70 s, respectively; p<0.01). No differences were observed in coronary microvascular function and diastolic left ventricular function between the 2 drugs and compared to baseline.

CONCLUSIONS

Our data show that ranolazine, but not ISMN, improved time to ischemia during EST. This effect, however, was independent of any effects on coronary microvascular and diastolic function.

Diagnostic role of echocardiography in patients admitted to the emergency room with suspect no-ST-segment elevation acute myocardial infarction

OBJECTIVE

We investigated whether echocardiography may help identify, among patients admitted with a suspect of non-ST-segment elevation acute myocardial infarction (NSTEMI), those with athero-thrombotic coronary artery disease (CAD).

PATIENTS AND METHODS

We studied consecutive patients admitted with a clinical suspect of first NSTEMI. Echocardiography was assessed within 24 hours from admission. Patients were divided into two groups, according to the results of coronary angiography: 1) patients with obstructive stenosis (≥ 50%) and/or images of thrombosis in one or more coronary arteries (CAD group); 2) patients with no evidence of obstructive coronary arteries (NOCAD group).

RESULTS

Of 101 patients enrolled in the study, 53 (52.5%) showed obstructive CAD and 48 (47.5%) NOCAD. At echocardiographic examination, regional wall motion abnormalities were found in 52.8% of patients in the CAD group and 43.7% in the NOCAD group (p=0.43). Left ventricle ejection fraction was 56.4±6.8 vs. 54.7±9.8% (p=0.30) and wall motion score index was 1.16±0.26 vs. 1.21±0.32 (p=0.39) in the two groups, respectively. A multivariable logistic regression independent predictors of obstructive CAD included age, male gender, typical angina, diabetes and hypertension.

CONCLUSIONS

Our data showed that, in patients with acute chest pain and increased serum troponin T concentration, routine standard echocardiography does not significantly improve the diagnostic accuracy for the presence of obstructive CAD.