Functional Mitral Regurgitation: A Link to Pulmonary Hypertension in Heart Failure With Preserved Ejection Fraction

Pulmonary Hypertension in Left Ventricular Valvular Diseases: A Comprehensive Review on Pathophysiology and Prognostic Value

Left ventricular (LV) valvular diseases, make up one of the most common etiologies for pulmonary hypertension (PH), and it is not well understood how and at which degree it affects prognosis. The aim of the present study was a comprehensive review of the pathophysiologic mechanism of PH in patients with LV valvular diseases and the prognostic value of baseline and post-intervention PH in patients undergoing interventional treatment. The pathophysiology of PH in patients with LV valvular diseases involves gradual elevation of left ventricular filling pressure and left atrial pressure, which are passively transmitted to the pulmonary circulation and raise pulmonary artery systolic pressure (PASP). A long-lasting exposure to elevated PASP progressively leads to initially functional and thereafter irreversible structural changes in the pulmonary vasculature, leading up to high pulmonary vascular resistance. Surgical treatment of severe LV valvular diseases is highly effective in patients without resting PH or those with exercise-induced PH (EIPH) before intervention. In the case of pre-operative PH, successful interventional therapy decreases PASP, but the post-operative cardiac and all-cause mortality remain higher compared to patients without pre-operative PH. Hence, it is of paramount importance to detect patients with severe LV valvulopathies before the development of PH, since they will get greater benefits from early intervention.

Impact of concomitant mitral valve surgery on the clinical outcomes of patients with moderate functional mitral regurgitation and HFpEF undergoing aortic valve replacement: a cohort study

BACKGROUND

Functional mitral regurgitation (FMR) worsens the prognosis of patients with heart failure with preserved ejection fraction (HFpEF). While concomitant mitral valve surgery (MVS) is recommended for severe FMR during aortic valve replacement (AVR), the optimal treatment of moderate FMR, especially in those with HFpEF, remains unclear. This study aimed to evaluate the effect of MVS in patients with moderate FMR and HFpEF undergoing AVR.

METHODS

A total of 212 consecutive patients (AVR: 34.0%, AVR-MVS: 66.0%) during 2010 and 2019 were enrolled. Survival outcomes were compared. Inverse probability treatment weighting (IPTW) was used to balance the baseline characteristics. Kaplan-Meier curve and log-rank test were applied to compare the survival outcomes. The primary endpoint was the overall mortality.

RESULTS

The mean age was 58.9 [Formula: see text] 11.9 years, and 27.8% of them were female. During a median follow-up of 16.4 months, AVR-MVS did not reduce the risk of mid-term MACCE (hazard ratio [HR]: 1.53, 95% confidence interval [CI]: 0.57-4.17, P_log-rank = 0.396), while it showed a tendency toward higher MACCE risk in the IPTW analysis (HR: 2.62, 95% CI: 0.84-8.16, P_log-rank = 0.096). In addition, AVR-MVS increased the risk of mortality as compared to isolated AVR (0 vs. 10%, P_log-rank = 0.016), which was sustained in the IPTW analysis  (0 vs. 9.9%, P_log-rank<0.001).

CONCLUSION

In patients with moderate FMR and HFpEF, isolated AVR might be more reasonable than AVR-MVS.

Mitral Regurgitation and Mortality Risk in Medicare Beneficiaries With Heart Failure and Preserved Ejection Fraction

The association of mitral regurgitation (MR) severity and mortality in heart failure with preserved ejection fraction (HFpEF) is uncertain. We sought to evaluate the relation between MR severity on transthoracic echocardiography (TTE) and subsequent all-cause mortality in Medicare beneficiaries with HFpEF. We linked 57,608 patients referred for TTE at Beth Israel Deaconess Medical Center to Medicare inpatient claims from 2003 to 2017. In those with a history of HF and a physician-reported left ventricular ejection fraction ≥50%, we evaluated the relation of MR severity and time to the primary end point of all-cause mortality using Kaplan-Meier methods. A total of 7,778 individuals (14.5%) met inclusion criteria (mean age 75.5 years ± 11.9, 55.9% female). Over a median follow-up of 8.1 years, 2,016 (25.9%) died at a median (interquartile range) of 1.7 (0.3 to 4.1) years. At 1 year, 15.8% with 3 to 4+ MR had died versus 10.5% with 0 to 2+ MR (hazard ratio 1.54, 95% confidence interval 1.22 to 1.95, p <0.001). After multivariable adjustment, 3 to 4+ MR continued to be associated with increased all-cause mortality (hazard ratio 1.48, 95% confidence interval 1.14 to 1.94, p = 0.004) except in the subset with atrial fibrillation (interaction p = 0.03) or recent (<3 months) HF hospitalization (p = 0.54). In conclusion, in this large, single-institution retrospective study of Medicare beneficiaries with HFpEF who underwent TTE, moderate-to-severe and severe MR were significantly associated with an increased risk of all-cause mortality after multivariable adjustment, except in those with atrial fibrillation or recent HF. Prospective studies are needed to assess the role of MR reduction in mitigating this risk.

Response to acute vasodilator challenge and haemodynamic modifications after MitraClip in patients with functional mitral regurgitation and pulmonary hypertension

The effectiveness of transcatheter edge-to-edge repair (TEER) in patients with functional mitral regurgitation (FMR) and pulmonary hypertension (PH) is still debated and pre-procedural predictors of haemodynamic improvement after TEER in this setting are currently unknown. We investigated whether normalization of pulmonary artery wedge pressure (PAWP) in response to sodium nitroprusside (SNP) during baseline right heart catheterization might be predictive of a favourable haemodynamic response to MitraClip in patients with FMR and PH. Among 22 patients enrolled, 13 had a positive response to SNP (responders), nine were non-responders. At 6-months follow-up, responders showed a 33% reduction in PAWP and a 25% reduction in mean pulmonary artery pressure (PAP) (P = 0.002 and 0.004, respectively); no significant change occurred in non-responders. In patients with FMR and PH, pre-procedural vasodilator challenge with SNP may help define patients who may have haemodynamic improvement after TEER.

Mitral Valve Prolapse and Its Motley Crew-Syndromic Prevalence, Pathophysiology, and Progression of a Common Heart Condition

Mitral valve prolapse (MVP) is a commonly occurring heart condition defined by enlargement and superior displacement of the mitral valve leaflet(s) during systole. Although commonly seen as a standalone disorder, MVP has also been described in case reports and small studies of patients with various genetic syndromes. In this review, we analyzed the prevalence of MVP within syndromes where an association to MVP has previously been reported. We further discussed the shared biological pathways that cause MVP in these syndromes, as well as how MVP in turn causes a diverse array of cardiac and noncardiac complications. We found 105 studies that identified patients with mitral valve anomalies within 18 different genetic, developmental, and connective tissue diseases. We show that some disorders previously believed to have an increased prevalence of MVP, including osteogenesis imperfecta, fragile X syndrome, Down syndrome, and Pseudoxanthoma elasticum, have few to no studies that use up-to-date diagnostic criteria for the disease and therefore may be overestimating the prevalence of MVP within the syndrome. Additionally, we highlight that in contrast to early studies describing MVP as a benign entity, the clinical course experienced by patients can be heterogeneous and may cause significant cardiovascular morbidity and mortality. Currently only surgical correction of MVP is curative, but it is reserved for severe cases in which irreversible complications of MVP may already be established; therefore, a review of clinical guidelines to allow for earlier surgical intervention may be warranted to lower cardiovascular risk in patients with MVP.

Valvular Disease and Heart Failure with Preserved Ejection Fraction

Heart failure with preserved ejection fraction (HFpEF) is a clinical syndrome of shortness of breath and/or exercise intolerance secondary to elevated left ventricular filling pressures at rest or with exertion either as a result of primary diastolic dysfunction (primary HFpEF) or secondary to specific underlying causes (secondary HFpEF). In secondary HFpEF, early intervention of underlying valvular heart disease generally improves symptoms and prolongs survival. In primary HFpEF, there is increasing awareness of the existence and prognostic implications of secondary atrioventricular valve regurgitation. Further studies will clarify their mechanisms and the effectiveness of valvular intervention in this intriguing HFpEF subgroup.

Mitral regurgitation and dyspnoea: the expanding role of mitral effective regurgitant orifice among un-selected patients

AIMS

Mitral regurgitation is frequent in the general population and among suspected heart failure patients; however, to what extent it contributes to dyspnoea is unclear. We hypothesized mitral regurgitation to have a role in determining dyspnoea in unselected ambulatory patients.

METHODS

Consecutive outpatients referred for echocardiography were retrospectively screened and included. We excluded patients with mitral stenosis or prosthesis, congenital heart disease, cardiac surgery (previous 6 months) and atrial fibrillation. Patients were classified into four dyspnoea grades based on how they perceived their disability. We assessed mitral regurgitation severity through the effective regurgitant orifice area (ERO).

RESULTS

One hundred and fifty-four patients (58% men; age 67 ± 14 years; mean ejection fraction 54 ± 12%) formed the study population; 76 (49%) classified asymptomatic (grade I), 63 (41%) dyspnoea grade II and 15 (10%) grade III; none was in grade IV. Mitral regurgitation was present in 102 patients (66%): primary in 14 (14%) and secondary in 88 (86%); among grades I, II and III patients, mitral regurgitation was present in 35 (46%; ERO 0.05 ± 0.10 cm), 52 (82%; ERO 0.10 ± 0.13 cm) and 15 (100%; ERO 0.20 ± 0.11 cm) patients, respectively (P < 0.0001). After adjusting for clinical (age, hypertension, ischemic heart disease, chronic kidney injury, chronic pulmonary disease) and echocardiographic confounders (ejection fraction, E/e'), ERO remained associated with symptoms presence (grade I versus II - III; P = 0.01 and P = 0.03, respectively).

CONCLUSION

Among unselected heterogeneous ambulatory patients, mitral ERO was associated with the presence of dyspnoea and could therefore help in identifying symptomatic patients and in clinical characterization of patients with perceived dyspnoea.

Prognostic impact of moderate mitral regurgitation on hospitalized heart failure patients with preserved ejection fraction: A report from the JASPER registry

A growing body of evidence suggests that mitral regurgitation (MR) is associated with higher mortality in heart failure patients with reduced ejection fraction. However, prognostic impact of MR on heart failure patients with preserved ejection fraction (HFpEF) has not been fully examined. The Japanese Heart Failure Syndrome with Preserved Ejection Fraction (JASPER) registry is a nationwide, observational, prospective registration of consecutive Japanese hospitalized HFpEF patients with LVEF ≥ 50%. Severe valvular heart disease was excluded from this cohort. We divided the consecutive 341 patients into two groups based on the severity of MR at discharge: no or mild MR group (n = 317) and moderate MR group (n = 24). Compared with no or mild MR group, moderate MR group showed larger left ventricular end-diastolic diameter (52 [48-59] vs. 46 [42-50] mm, P < 0.001), left ventricular systolic diameter (35 [30-37] vs. 29 [26-34] mm, P = 0.006), left atrial diameter (49 [46-56] vs. 45 [40-50] mm, P < 0.001), and higher tricuspid regurgitation peak gradient (33 [25-40] vs. 27 [21-33] mmHg, P = 0.012). In contrast, levels of plasma B-type natriuretic peptide and left ventricular ejection fraction were comparable between the two groups. In the follow-up period (median 738 days), there were 57 all-cause deaths. In the Kaplan-Meier analysis, all-cause mortality was higher in moderate MR group than in no or mild MR group (log-rank P = 0.023). In the Cox proportional hazard analysis, moderate MR at discharge was a predictor of all-cause mortality (hazard ratio 2.256, 95% confidence interval 1.035-4.917, P = 0.041). Moderate MR at discharge is associated with adverse prognosis in hospitalized patients with HFpEF.

Mitral regurgitation, left atrial structural and functional remodelling and the effect on pulmonary haemodynamics

AIMS

To assess the association between mitral regurgitation (MR) and left atrial (LA) structural and functional remodelling and their effect on pulmonary haemodynamics.

METHODS AND RESULTS

Consecutive unselected patients undergoing comprehensive echocardiography were enrolled. Parameters of cardiac structure and function were obtained as well as mitral effective regurgitant orifice area (ERO) and estimation of pulmonary artery systolic pressure (PASP). Measures of LA structure [LA volume (LAV)] and function [peak atrial longitudinal strain (PALS), peak atrial contraction strain (PACS) and conduit strain (CS)] were also calculated. The study population included 102 patients (mean age 70 ± 14 years, 42% women), with a mean ejection fraction of 52 ± 13%. MR was classified as organic due to mitral valve prolapse in 14 patients (14%) and functional in 88 patients (86%). Mean ERO was 0.12 ± 0.12 cm² and 86 patients (84%) had an ERO ≤0.2 cm² . ERO was significantly associated with worse measures of LA structure and function. Despite the low burden of MR, the association remained significant after adjusting for clinical and echocardiographic confounders (β: 3.7, P = 0.022 for LAV; β: -3.0, P = 0.003 for PALS; β: -1.8, P = 0.027 for PACS) and was significantly related with functional MR (P for interaction <0.001). ERO was also significantly associated with PASP, and measures of LA function (PALS and PACS) significantly modified this relationship (P for interaction <0.001).

CONCLUSIONS

Even a mild degree of MR contributes to LA remodelling and this relationship plays an active role in pulmonary circulation, suggesting a potential mechanism by which these parameters contribute to the development of heart failure.

The Right Heart-Pulmonary Circulation Unit and Left Heart Valve Disease

Valvular heart disease (VHD) is frequently accompanied by pulmonary hypertension (PH). In asymptomatic patients, PH is rare, although the exact prevalence is unknown and mainly stems from the severity of the VHD and the presence of diastolic dysfunction. PH can also be depicted during exercise echocardiography. PH either at rest or during exercise is also a powerful determinant of outcome and is independently associated with reduced survival, regardless of the severity of the underlying valvular pathology. Therefore, because PH is a marker of poor prognosis, assessment of PH in VHD is crucial for risk stratification and management of patients with VHD.

Pulmonary Hypertension in Heart Failure Patients: Pathophysiology and Prognostic Implications

Pulmonary hypertension (PH) due to left heart disease (LHD), i.e., group 2 PH, is the most common reason for increased pressures in the pulmonary circuit. Although recent guidelines incorporate congenital heart disease in this classification, left-sided heart diseases of diastolic and systolic origin including valvular etiology are the vast majority. In these patients, an increased left-sided filling pressure triggers a multistage hemodynamic evolution that ends into right ventricular failure through an initial passive increase in pulmonary artery pressure complicated over time by pulmonary vasoconstriction, endothelial dysfunction, and remodeling of the small-resistance pulmonary arteries. Regardless of the underlying left heart pathology, when present, PH-LHD is associated with more severe symptoms, worse exercise tolerance, and outcome, especially when right ventricular dysfunction and failure are part of the picture. Compared with group 1 and other forms of pulmonary arterial hypertension, PH-LHD is more often seen in elderly patients with a higher prevalence of cardiovascular comorbidities and most, if not all, of the features of metabolic syndrome, especially in case of HF preserved ejection fraction. In this review, we provide an update on current knowledge and some potential challenges about the pathophysiology and established prognostic implications of group 2 PH in patients with HF of either preserved or reduced ejection fraction.

Functional anatomy and pathophysiologic principles in mitral regurgitation: Non-invasive assessment

Mitral regurgitation (MR) is the most prevalent cause of valvular heart disease (VHD) in western countries. In the Euro Heart Survey on VHD, MR was the second most common heart VHD requiring surgery. It is also the most common form of VHD in community and population-based studies from the United States. The categorization of MR based on causes and mechanisms is a major determinant of clinical outcome, of possible therapies for the MR and of the effectiveness of these therapies. Surgical mitral valve (MV) repair has been shown to improve survival in patients with severe primary MR compared with MV replacement. In addition, new percutaneous repair and replacement procedures have been recently developed. Hence, accurate understanding of the functional anatomy of the MV and the pathophysiologic principles underlying MR is needed to appropriately target valve lesions. Recent advances in cardiac imaging have allowed to deeply strengthen the knowledge of the function of the MV. The present review aims at describing the functional anatomy and pathophysiology of MR through different cardiac imaging modalities.

Pulmonary hypertension due to left heart disease

Pulmonary hypertension due to left heart disease, also known as group 2 pulmonary hypertension according to the European Society of Cardiology/European Respiratory Society classification, is the most common cause of pulmonary hypertension. In patients with left heart disease, the development of pulmonary hypertension favours right heart dysfunction, which has a major impact on disease severity and outcome. Over the past few years, this condition has been considered more frequently. However, epidemiological studies of group 2 pulmonary hypertension are less exhaustive than studies of other causes of pulmonary hypertension. In group 2 patients, pulmonary hypertension may be caused by an isolated increase in left-sided filling pressures or by a combination of this condition with increased pulmonary vascular resistance, with an abnormally high pressure gradient between arteries and pulmonary veins. A better understanding of the conditions underlying pulmonary hypertension is of key importance to establish a comprehensive diagnosis, leading to an adapted treatment to reduce heart failure morbidity and mortality. In this review, epidemiology, mechanisms and diagnostic approaches are reviewed; then, treatment options and future approaches are considered.

Mitral Regurgitation and Increased Risk of All-Cause and Cardiovascular Mortality in Patients with Type 2 Diabetes

BACKGROUND

Mitral regurgitation is the most common heart valve disease in the general population, but little is known about the prevalence and prognostic implications of mitral regurgitation in patients with type 2 diabetes.

METHODS

We retrospectively analyzed the data from 814 outpatients with type 2 diabetes who had undergone a conventional echocardiography for clinical reasons during the years 1992-2007. Mitral regurgitation was evaluated by using an integrated multiparametric echocardiographic approach. The study outcomes were all-cause and cardiovascular mortality.

RESULTS

At baseline, 261 (32%) patients had mitral regurgitation (25% mild, 5% moderate, and 2% severe). Over a mean follow-up of 9 years, 120 (14%) patients died, 50 of them from cardiovascular causes. Compared with those without valve disease, patients with mild mitral regurgitation had a 3.3-fold increased risk of all-cause mortality, whereas those with moderate-to-severe mitral regurgitation had a 5.1-fold increased risk of all-cause mortality. Results remained statistically significant after adjustment for multiple potential confounders. Similar results were found for cardiovascular mortality.

CONCLUSIONS

Mitral regurgitation is a common pathologic condition in patients with type 2 diabetes and is independently associated with an increased risk of both all-cause and cardiovascular mortality, even if the severity of mitral regurgitation is mild.

Evolving Concepts of Pulmonary Hypertension Secondary to Left Heart Disease

Pulmonary hypertension associated with left heart disease is the most common form of pulmonary hypertension. Although its pathophysiology remains incompletely understood, it is now well recognized that the presence of pulmonary hypertension is associated with a worse prognosis. Right ventricular failure has independent and additive prognostic value over pulmonary hypertension for adverse outcomes in left heart disease. Recently, several new terminologies have been introduced to better define and characterize the nature and severity of pulmonary hypertension. Several new treatment options including the use of pulmonary arterial hypertension specific therapies are being considered, but there is lack of evidence. Here, we review the recent advances in this field and summarize the diagnostic and therapeutic modalities of use in the management of pulmonary hypertension associated with left heart disease.

Pulmonary Hypertension in Aortic Stenosis and Mitral Regurgitation: Rest and Exercise Echocardiography Significance

Valvular heart disease is a common cause of increased mean pulmonary artery pressure (PAP). Aortic stenosis and mitral regurgitation are frequently accompanied by pulmonary hypertension (PH), especially when they are severe and symptomatic. In asymptomatic patients, PH is rare, though the exact prevalence is unknown and mainly stems from the severity of the valvular heart disease and the presence of diastolic dysfunction. Exercise echocardiography has recently gained interest in depicting PH. In these asymptomatic patients, exercise PH is observed in about >40%. Either PH at rest (systolic PAP >50 mmHg) or during exercise (systolic PAP >60 mmHg) is a powerful determinant of outcome and is independently associated with reduced survival, regardless of the severity of the underlying valvular pathology.

Exercise echocardiography for structural heart disease

Since the introduction of transcatheter structural heart intervention, the term "structural heart disease" has been widely used in the field of cardiology. Structural heart disease refers to congenital heart disease, valvular heart disease, and cardiomyopathy. In structural heart disease, valvular heart disease is frequently identified in the elderly. Of note, the number of patients who suffer from aortic stenosis (AS) and mitral regurgitation (MR) is increasing in developed countries because of the aging of the populations. Transcatheter aortic valve replacement and percutaneous mitral valve repair has been widely used for AS and MR, individually. Echocardiography is the gold standard modality for initial diagnosis and subsequent evaluation of AS and MR, although the difficulties in assessing patients with these diseases still remain. Here, we review the clinical usefulness and prognostic impact of exercise echocardiography on structural heart disease, particularly on AS and MR.

Purification and Comparative Assay of Human Mitochondrial Single-Stranded DNA-Binding Protein

The mitochondrial single-stranded DNA-binding protein (mtSSB) coordinates the function of replisome components at the mitochondrial replication fork. In recent years, it has been demonstrated that mtSSB stimulates the activities of DNA polymerase γ (Pol γ) and mitochondrial DNA (mtDNA) helicase in a concentration-dependent manner. Here we present a new approach to purify the human mtSSB and our standard assays to evaluate its biochemical properties, including a Gel Mobility Shift Assay (GMSA) to assess single-stranded DNA (ssDNA) binding activity, and an assay to assess SSB stimulation of Pol γ activity.

Vascular and Microvascular Endothelial Function in Heart Failure With Preserved Ejection Fraction

BACKGROUND

Assessment of vascular endothelial function lacks consistency, and microvascular endothelial function has been only partly assessed in heart failure with preserved ejection fraction (HFpEF).

METHODS

The study population consisted of 90 patients: 45 had well documented HFpEF, and 45 had hypertension and no history or evidence of heart failure. Patients with hypertension but no heart failure were matched with HFpEF patients for age, sex, and diabetes. They served as control subjects. All patients underwent 2-dimensional Doppler echocardiography and vascular function measurements, including assessment of arterial wave reflections and arterial stiffness, brachial artery flow-mediated dilation (FMD), and forearm cutaneous blood flow with the use of a laser Doppler flow probe at rest and after release of arterial occlusion for 5 minutes.

RESULTS

Brachial artery FMD was lower in HFpEF than in control subjects (median (IQR) 3.6 (0.4-7.4) vs. 7.2 (3.2-17.2)%, P = .001). Forearm cutaneous blood flow at rest was similar in HFpEF and control subjects (P = .68). After release of arterial occlusion, forearm cutaneous peak blood flow was lower in HFpEF than in control subjects (P = .03). Estimated aortic systolic and mean blood pressures were similar in HFpEF and control subjects, whereas pulse pressure and pressure augmentation were greater in HFPEF than in control subjects (both P < .05).

CONCLUSION

Compared with hypertensive control subjects, patients with HFpEF had a depressed endothelial function in the forearm vasculature and microvasculature.

Beneficial Effects of Positive Airway Pressure Therapy for Sleep-Disordered Breathing in Heart Failure Patients With Preserved Left Ventricular Ejection Fraction

BACKGROUND

Right-heart dysfunction is associated with poor prognosis in heart failure with preserved left ventricular ejection fraction (HFpEF). It remains unclear whether sleep-disordered breathing (SDB) treatment using positive airway pressure (PAP) improves right-heart and pulmonary function and exercise capacity and reduces mortality rates of HFpEF patients.

HYPOTHESIS

PAP may improve right-heart and pulmonary function, exercise capacity and prognosis in HFpEF patients with SDB.

METHODS

One hundred nine consecutive patients with HFpEF (left ventricular ejection fraction >50%) and moderate to severe SDB (apnea-hypopnea index ≥15/h) treated with medications were divided into 2 groups: 31 patients with PAP (PAP group) and 78 patients without PAP (non-PAP group). Right ventricular fractional area change (RV-FAC), tricuspid valve regurgitation pressure gradient (TR-PG), tricuspid valve E/E', forced expiratory volume in 1 second/forced vital capacity (FEV1 /FVC), percentage of vital capacity, and peak VO2 were determined before and 6 months later, and all-cause mortality was followed up for 916 days.

RESULTS

All parameters improved in the PAP group (RV-FAC, 36.0% -46.5%; TR-PG, 31.1 mm Hg-22.4 mm Hg; tricuspid valve E/E', 7.8-5.1; FEV1 /FVC, 83.9%-89.8%; percentage of vital capacity, 83.5%-89.9%; and peak VO2 , 16.6 mL/kg/min-19.6 mL/kg/min; P <0.05, respectively) but not in the non-PAP group. Importantly, all-cause mortality was significantly lower in the PAP group than in the non-PAP group (0% vs 12.8%; log-rank P = 0.014).

CONCLUSIONS

Positive airway pressure improves right-heart and pulmonary function and exercise capacity and may reduce all-cause mortality in patients with HFpEF and SDB.

Integration of exercise evaluation into the algorithm for evaluation of patients with suspected heart failure with preserved ejection fraction

Approximately half of all patients with heart failure (HF) have a preserved left ventricular ejection fraction (HFPEF) and the prevalence of this form of HF is increasing. Although dyspnoea on exertion and diminished functional capacity is the key symptom of patients with HFPEF, current diagnostic criteria focus on resting indices of ventricular function. Specifically, current proposed criteria for the diagnosis of HFPEF, include clinical signs of HF; normal left ventricular systolic function; and evidence of abnormal diastolic performance and/or altered natriuretic peptides. By contrast, recent studies demonstrate that the key pathophysiologic features of HFPEF may not be evident at rest, and can only be detected during exertion. This review addresses the potential role of exercise testing using invasive haemodynamic or echocardiographic assessment in patients with suspected HFPEF in which current diagnostic criteria are not met.

Management of pulmonary hypertension in left heart disease

Pulmonary hypertension (PH) due to left heart disease is classified as group II according to the Dana Point classification, which includes left ventricular systolic and/or diastolic left heart failure, and left-sided valvular disease. PH due to left heart disease is the most common cause and when present, especially with right ventricular dysfunction, is associated with a worse prognosis. Left heart disease with secondary PH is associated with increased left atrial pressure, which causes a passive increase in pulmonary pressure. Passive PH could be superimposed by an active protective, and in some patients by an ‘out of proportion’, elevated precapillary pulmonary vasoconstriction and vascular remodelling which leads to greater or lesser further increase of the pulmonary artery pressure. In this review, epidemiological and pathophysiologic mechanisms for the development of group II PH are summarized. The conflicting data about the haemodynamic and possible parameters to diagnose passive versus reactive and ‘out of proportion’ PH are presented. The different therapeutic concepts, along with novel treatment strategies, are reviewed in detail and critically discussed regarding their effectiveness and safety.

Secondary Mitral Regurgitation in Heart Failure with Reduced or Preserved Left Ventricular Ejection Fraction

Secondary mitral regurgitation (MR) has been extensively studied in heart failure due to reduced ejection fraction. In contrast, the occurrence and the pathogenesis of secondary MR are much less known in heart failure with preserved ejection fraction (HFpEF). The present review aimed at describing this common but ignored feature of HFpEF.

[Heart failure with preserved ejection fraction: a systemic disorder?]

When the syndrome of heart failure (HF) is due to left ventricular (LV) systolic dysfunction the clinical manifestations and natural history of the syndrome depend primarily on the severity of LV systolic dysfunction. In contrast, when the syndrome is attributed to LV diastolic dysfunction multiple comorbidities are responsible for the clinical manifestations and the natural history of the syndrome. The present review underscores the multifactorial pathogenesis of the syndrome of HF associated with LV diastolic dysfunction that nowadays is more properly referred to as HF with preserved LV ejection fraction (HFpEF) than to diastolic HF. The prognosis is similarly poor whether HF is due to systolic dysfunction or associated with diastolic dysfunction. The cause of death that is commonly non-cardiovascular in HFpEF supports the pathogenic importance of comorbidities in this condition. Hypertension, chronic kidney disease (CKD), diabetes, obesity and sleep disorder breathing are among the most frequent comorbidities in HFpEF. These comorbidities account for the multiple clinical presentations of the syndrome of HFpEF. Limited functional capacity is in HFpEF largely related to the downward spiral between CKD mediated fluid accumulation and LV stiffness as well as altered ventricular-vascular coupling. The diagnosis of HFpEF currently relies on 2D-Doppler echocardiography findings of impaired LV relaxation and increased LV stiffness and to a lesser extent on biomarkers. Owing to both lack of stringent inclusion and exclusion enrollment criteria and mistaken therapeutic target, placebo-controlled randomized therapeutic trials have been so far negative in HFpEF.