Standardization of normal values for cardiac chamber size in echocardiography

Echocardiography is used worldwide to evaluate cardiac size and function. To determine what values are abnormal, it is essential to establish normal reference values for echocardiography. The current guidelines for chamber quantification specify normative values for cardiac chambers and recommend that gender and body size be taken into account. However, these normative data were established using databases for which a variety of measurement methods were used and the majority of subjects consisted of Whites in Europe and the United States. However, several regional studies from other countries suggest that cardiac size varies globally. To overcome these limitations, the Normal Reference Ranges for Echocardiography study and the World Alliance of Societies of Echocardiography Normal Values study have recently been conducted to examine similarities and differences in cardiac chamber size and to establish normal reference values while taking worldwide diversity into account. The results from these studies have demonstrated that standardization of normal reference values for cardiac size is important. This review article aims to summarize the current status of normative echocardiographic values for cardiac chamber size.

Association between pre-operative right ventricular impairment on transthoracic echocardiography and outcomes after conventional and minimally invasive mitral valve surgery

BACKGROUND

Right ventricular (RV) impairment may have prognostic value in patients undergoing mitral valve surgery. It is unclear whether RV dysfunction predicts long-term mortality, especially in the era of minimally invasive mitral surgery.

METHODS

We performed a retrospective analysis of consecutive patients referred for conventional (via sternotomy) and minimally invasive mitral valve surgery (MIMVS) between 01 January 2013 and 29 August 2018 in a tertiary cardiac centre. We truncated follow-up times at 25 March 2020. RV impairment was defined by reduced RV longitudinal function (TAPSE <17 mm) and/or dilated basal RV diameter (RVD1 > 42 mm). Primary outcome was all-cause mortality.

RESULTS

The study cohort included 359 patients followed up for a median period of 4.2 (1.8) years. MIMVS approach was performed in 127 (35.4%) and conventional approach in 232 (64.6%) patients of whom 36 (28%) and 45 (19%), respectively, had RV impairment. EuroSCORE II was significantly higher in patients with RV impairment compared with patients with preserved RV function, irrespective of the surgical approach. Consequently, in both groups, patients with RV impairment had significantly higher mortality compared to patients with preserved RV function. RV impairment adjusted for EuroSCORE II predicted mortality in the whole cohort (HR 2.139, 95% CI 1.249-3.663) and in conventional approach (HR 2.361, 95% CI 1.249-4.465) in contrast to MIMVS (HR 1.570, 95% CI 0.493-4.997).

CONCLUSION

In this real world cohort, patients with RV impairment and/or dilation had reduced long-term survival following both conventional surgery and MIMVS. Patients should be referred to surgery prior to worsening of RV function.

The Right Ventricle in the Trans-Catheter Era: A Perspective for Planning Interventions

Dysfunction of the right ventricle (RV) is common in patients with advanced left-sided valve disease and the significant impact of RV dysfunction on both short and long-term outcome is well established. However, considerations of RV function are largely absent in current management guidelines for valve disease and cardiac procedural risk models. As the indications and use of trans-catheter therapies rapidly expand for patients with acquired valvular disease, it is critical for clinicians to understand and consider RV function when making decisions for these patients. This review summarizes contemporary data on the assessment of RV function, the prognostic importance of baseline RV dysfunction on surgical and transcatheter procedures for acquired left-sided valvular disease, and the relative impact of these interventions on RV function. Baseline RV dysfunction is a powerful predictor of poor short- and long-term outcome after any therapeutic intervention for acquired left-sided cardiac valve disease. Surgical intervention for aortic or mitral valve disease is associated with a significant but transient decline in RV function, whereas trans-catheter procedures generally do not appear to have detrimental effects on either longitudinal or global RV function. Guidelines for therapy in patents with acquired left-sided valvular disease should account for RV dysfunction. Whereas surgical intervention in these patients leads to a predictable decline in RV function, trans-catheter therapies largely do not appear to have this effect. Further study is needed to determine the impact of these findings on current practice.

Speckle tracking echocardiography in primary mitral regurgitation: should we reconsider the time for intervention?

Thanks to the improvement in mitral regurgitation (MR) diagnostic and therapeutic management, with the introduction of minimally invasive techniques which have considerably reduced the individual surgical risk, the optimization of the timing for MR “open” or percutaneous surgical treatment has become a main concern which has highly raised scientific interest. In fact, the current indications for intervention in MR, especially in asymptomatic patients, rely on echocardiographic criteria with high severity cut-offs that are fulfilled only when not only mitral valve apparatus but also the cardiac chambers’ structure and function are severely impaired, which results in poor benefits for post-operative clinical outcome. This led to the need of new indices to redefine the optimal surgical timing in these patients. Speckle tracking echocardiography provides early markers of cardiac dysfunction due to subtle myocardial impairment; therefore, it could offer pivotal information in this setting. In fact, left ventricular and left atrial strains have already shown evidence about their usefulness in recognizing MR impact not only on symptoms and quality of life but also on cardiovascular events and new-onset atrial fibrillation in these patients. Moreover, right ventricular strain could be used to identify those patients with advanced cardiac damage and different grades of right ventricular dysfunction, which entails higher risks for cardiac surgery that could overweigh surgical benefits. This review aims to describe the importance of reconsidering the timing of intervention in MR and to analyze the potential additive value of speckle tracking echocardiography in this clinical setting.

Prognostic Value of Late Gadolinium Enhancement in Postoperative Morbidity following Mitral Valve Surgery in Rheumatic Mitral Stenosis

Myocardial fibrosis in rheumatic mitral stenosis (MS) is caused by chronic inflammatory process. Its occurrence may lead to hemodynamic problems, especially after cardiac surgery. Myocardial fibrosis predicts worse morbidity after cardiac surgery, notably in coronary heart disease and aortic valve abnormalities. However, this issue has not been explored yet among patients with rheumatic MS. The aim of the study was to investigate prognostic impact of myocardial fibrosis to postoperative morbidity after mitral valve surgery in patients with rheumatic MS. This is a prospectively enrolled observational study of 47 consecutive rheumatic MS patients. All patients had preoperative evaluation with cardiac magnetic resonance imaging (CMR) including late gadolinium enhancement (LGE) protocol for left ventricular myocardial fibrosis assessment prior to mitral valve surgery. All patients were followed during hospitalization period. Postoperative morbidities were defined as stroke, renal failure, and prolonged mechanical ventilation. This study involved 33 women (70.2%) and 14 men (29.8%) with a mean age of 46 ± 10 years. Preoperative myocardial fibrosis was identified in 43 patients (91.5%). Estimated fibrosis volume ranged from 0% to 12.8% (median 2.8%). Postoperative morbidities occurred in 11 patients (23.4%). Significant mean difference of myocardial fibrosis volume was observed between patients with and without morbidity after mitral valve surgery (5.97 ± 4.16% and 3.12 ± 2.62%, p  = 0.04). This significant association was allegedly influenced by different postoperative hemodynamic changes between the two groups. More extensive myocardial fibrosis is associated with postoperative morbiditiy after mitral valve surgery in patients with rheumatic MS.

Right Ventricular Function in Left Heart Disease

Right ventricular (RV) function is an independent prognostic factor for short- and long-term outcomes in cardiac surgical patients. Patients with mitral valve (MV) disease are at increased risk of RV dysfunction before and after MV operations. Yet RV function is not part of criteria for decision making or risk stratification in this setting. The role of MV disease in the development of pulmonary hypertension (PHTN) and the ultimate impact of PHTN on RV function have been well described. Nonetheless, there are other mechanisms by which MV disease and MV surgery affect RV performance. Research suggests that PHTN may not be the most important determinant of RV dysfunction. Both RV dysfunction and PHTN have independent prognostic significance. This review explores the unique anatomic and functional features of the RV and the pathophysiologic and prognostic implications of RV dysfunction in patients with MV disease in the perioperative period.

Right ventricular exercise contractile reserve and outcomes after early surgery for primary mitral regurgitation

Objective

To assess if the lack of development of right ventricular (RV) contractile reserve during exercise echocardiography (ex-echo) might be a predictor of postoperative major adverse cardiovascular events (MACEs) in patients with primary mitral regurgitation (pMR) undergoing early surgery.

Methods

Comprehensive resting and ex-echo were performed in 142 asymptomatic patients (58±21 years, 68% men, New York Heart Association functional class ≤2) with isolated severe pMR and preserved left ventricular (LV) function (LV ejection >60%, LV end-systolic diameter <45 mm) undergoing mitral valve replacement (n=20) or repair. Postoperative MACEs were defined as occurrence of atrial fibrillation, stroke, cardiac-related hospitalisation or death. RV function was evaluated at rest in every patient during ex-echo by measuring their tricuspid annular plane systolic excursion (TAPSE) value.

Results

After median follow-up of 30 months (IQR 16–60 months), MACEs occurred in 48 (34%) patients. Using Bayesian model averaging, among all the characteristics including the type of surgery, exercise TAPSE (ex-TAPSE) emerged as the most likely predictor of prognosis (HR 0.91, 95% CI 0.86 to 0.96). Other probable predictors were exercise fractional area change (HR 0.02, 95% CI 0.00 to 0.80), male gender (HR 0.40, 95% CI 0.21 to 0.75) and RV basal diameter (HR 1.06, 95% CI 0.98 to 1.14). In the receiver operating characteristic curve analysis, an ex-TAPSE value of <26 mm (sensitivity 73% (95% CI 61 to 84) and specificity of 86% (95% CI 77% to 93%)) defined RV dysfunction. Event-free survival at 5 years was significantly lower in the patient group that exhibited no development of RV contractile reserve during exercise: 43.9% (95% CI 31.3 to 61.4) vs 75.8% (95% CI 64.8 to 88.7).

Conclusion

Lack of development of exercise-induced RV contractile reserve is a prognostic predictor in patients with severe pMR undergoing early mitral valve surgery.

Additive and independent prognostic role of abnormal right ventricle and pulmonary hypertension in mitral-tricuspid surgery

OBJECTIVE

To evaluate the additive and independent prognostic value of abnormal right ventricle (aRV) and pulmonary hypertension (PH) in patients undergoing mitral-tricuspid surgery.

METHODS

From January 2009 to December 2012, 541 patients underwent mitro-tricuspid surgery. The entire cohort was divided into 6 subgroups: 63 cases had normal RV and no PH (Group A), 180 normal RV but moderate PH (Group B), 101 normal RV but severe PH (Group C), 15 abnormal RV and no-PH (Group D), 86 abnormal RV and moderate PH (Group E) and 96 abnormal RV and severe PH (Group F).

RESULTS

Forty-two (7.8%) patients died in hospital due to any cause: 1.6% in group A, 3.9% in group B, 8.9% in group C, 13.3% in group D, 9.3% in group E, 15.6% in group E, p = 0.005. Among 78 patients with no-PH, mortality was significantly higher in patients with aRV (1.6%vs 13.3%. p = 0.03). Among 344 patients with normal RV, mortality was significantly higher in patients with severe PH (1.6% vs 3.9% vs 8.9%. p = 0.03). Comparing the presence of both abnormal RV and severe PH with the remaining patients, mortality was significantly higher in the first group (15.6% 6.1%, p = 0.004). Multivariable analysis confirmed either the independent or the additive role of RV and PH.

CONCLUSIONS

In patients undergoing mitral-tricuspid valve surgery, the presence of either RV dysfunction/dilatation or severe pulmonary hypertension, might play an independent prognostic role for mortality. The worst scenario is surely the contemporary presence of both conditions.

The Dark Side of the Moon: The Right Ventricle

The aim of this review article is to summarize current knowledge of the pathophysiology underlying right ventricular failure (RVF), focusing, in particular, on right ventricular assessment and prognosis. The right ventricle (RV) can tolerate volume overload well, but is not able to sustain pressure overload. Right ventricular hypertrophy (RVH), as a response to increased afterload, can be adaptive or maladaptive. The easiest and most common way to assess the RV is by two-dimensional (2D) trans-thoracic echocardiography measuring surrogate indexes, such as tricuspid annular plane systolic excursion (TAPSE), fractional area change (FAC), and tissue Doppler velocity of the lateral aspect of the tricuspid valvular plane. However, both volumes and function are better estimated by 3D echocardiography and cardiac magnetic resonance (CMR). The prognostic role of the RV in heart failure (HF), pulmonary hypertension (PH), acute myocardial infarction (AMI), and cardiac surgery has been overlooked for many years. However, several recent studies have placed much greater importance on the RV in prognostic assessments. In conclusion, RV dimensions and function should be routinely assessed in cardiovascular disease, as RVF has a significant impact on disease prognosis. In the presence of RVF, different therapeutic approaches, either pharmacological or surgical, may be beneficial.

Five-year survival of patients with chronic systolic heart failure of ischemic and non-ischemic etiology: analysis of prognostic factors

INTRODUCTION

Despite advances in pharmacotherapy, electrotherapy and interventional treatment, chronic heart failure (HF) is still associated with poor long-term outcome.

AIM OF THE STUDY

To determine the death rate and risk factors in patients with HF of ischemic and non-ischemic etiology in five-year follow-up.

MATERIAL AND METHODS

Consecutive patients with chronic systolic HF hospitalized in the period 2006-2008 were analyzed retrospectively. Study exclusion criteria were: infections (< 3 months before hospitalization), hemodynamically significant valve disease, advanced chronic kidney disease, liver cirrhosis and neoplastic diseases (< 5 years before hospitalization).

RESULTS

The analysis encompassed 266 patients divided into two groups: Group A, with HF of ischemic etiology (n = 157), and Group B, with HF of non-ischemic etiology (n = 109). Mortality was significantly higher in Group A than in Group B (49% vs. 28.4%, p = 0.001). The independent risk factors for death in Group A were: New York Heart Association (NYHA) class (HR = 1.81; p < 0.001); concentrations of high-sensitivity C-reactive protein (hs-CRP) (HR = 1.01; p < 0.05), fibrinogen (HR = 1.04; p < 0.001) and N-terminal prohormone brain natriuretic peptide (NT-proBNP) (HR = 1.02; p < 0.001); and right ventricular end-diastolic diameter (RVEDd) (HR = 1.07; p < 0.01). In Group B they were age (HR = 1.07; p < 0.05) and NT-proBNP concentration (HR = 1.03; p < 0.001).

CONCLUSIONS

Mortality was significantly lower in Group B than in Group A. The independent risk factors for death in Group B were age and NT-proBNP serum concentration, whilst in Group A they were NYHA class, serum concentrations of hs-CRP, NT-proBNP and fibrinogen, and RVEDd.

Reference values of right ventricular end-diastolic area defined by ethnicity and gender in a young adult population: the CARDIA study

BACKGROUND

Despite increasing availability of three-dimensional imaging modalities for estimating right ventricular (RV) size, linear and two-dimensional measures of RV size are the most universally accessible clinical methods. Right ventricular end-diastolic area (RVED area) is known to identify pulmonary pathologies and have prognostic value for cardiovascular mortality in various disease states. To date, there is a paucity of adequately powered studies to define gender- and ethnicity-related differences in normal RVED area. Therefore, we derived gender-based normative values for echocardiographic measurements of RVED area, in a large bi-racial cohort of young adults.

METHODS

Healthy young adults participants (n = 2088) in the Coronary Artery Risk Development in Young Adults (CARDIA) study, aged 23-35 years, at the time of echocardiogram, were evaluated. RVED area was stratified according to gender and race. The contributions of clinical, allometric and left heart morphology and function to the variability in RVED area were determined.

RESULTS

RVED area in males was significantly larger than in females of similar age, but whites had similar values compared to same-gender blacks. RVED area for men and women of >24.7 cm(2) and 20.7cm(2) , or RVED area indexed to BSA (cm(2) /m(2) ) of >12.6 and >11.7, respectively, are at the 97.5th percentile of normal values. RVED area correlated significantly with left ventricular volume and left atrial size. Lung capacity measured as FVC showed significant body size adjusted correlation with RVED area only in black males.

CONCLUSIONS

This study provides normative values for echocardiographically defined RV end-diastolic area, and highlights the necessity to use gender-specific normative values.