Prognostic implications of pulmonary hypertension in patients with severe aortic stenosis

Impact of pulmonary hypertension on short-term outcomes in patients undergoing surgical aortic valve replacement for severe aortic valve stenosis

OBJECTIVES

In patients with left heart disease and severe aortic stenosis (AS), pulmonary hypertension (PH) is a common comorbidity and predictor of poor prognosis. Untreated AS aggravates PH leading to an increased right ventricular afterload and, in line to right ventricular dysfunction. The surgical benefit of aortic valve replacement (AVR) in elderly patients with severe AS and PH could be limited due to the multiple comorbidities and poor outcomes. Therefore, we purposed to investigate the impact of PH on short-term outcomes in patients with moderate to severe AS who underwent surgical AVR in our heart center.

METHODS

In this study we retrospectively analyzed a cohort of 99 patients with severe secondary post-capillary PH who underwent surgical AVR (AVR + PH group) at our heart center between 2010 and 2021 with a regard to perioperative outcomes. In order to investigate the impact of PH on short-term outcomes, the control group of 99 patients without pulmonary hypertension who underwent surgical AVR (AVR group) at our heart center with similar risk profile was accordingly analyzed regarding pre-, intra- and postoperative data.

RESULTS

Atrial fibrillation occurred significantly more often (p = .013) in patients who suffered from PH undergoing AVR. In addition, the risk for cardiac surgery (EUROSCORE II) was significantly higher (p < .001) in the above-mentioned group. Likewise, cardiopulmonary bypass time (p = .018), aortic cross-clamp time (p = .008) and average operation time (p = .009) were significantly longer in the AVR + PH group. Furthermore, the in-hospital survival rate was significantly higher (p = .044) in the AVR group compared to the AVR + PH group. Moreover, the dialysis rate was significantly higher (p < .001) postoperatively in patients who suffered PH compared to the patients without PH undergoing AVR.

CONCLUSION

In our study, patients with severe PH and severe symptomatic AS who underwent surgical aortic valve replacement showed adverse short-term outcomes compared to patients without PH.

Prevalence of pulmonary hypertension in aortic stenosis and its influence on outcomes

OBJECTIVE

The significance of pulmonary hypertension (PHT) complicating aortic stenosis (AS) is poorly characterised. In a large cohort of adults with at least moderate AS, we aimed to describe the prevalence and prognostic importance of PHT in such patients.

METHODS

In this retrospective study, we analysed the National Echocardiography Database of Australia (data from 2000 to 2019). Adults with an estimated right ventricular systolic pressure (eRVSP), left ventricular ejection fraction (LVEF) >50% and with moderate or greater AS were included (n=14 980). These subjects were then categorised according to their eRVSP. The relationship between PHT severity and mortality outcomes were evaluated (median follow-up of 2.6 years, IQR 1.0-4.6 years).

RESULTS

Subjects were aged 77±13 years and 57.4% were female. Overall, 2049 (13.7%), 5085 (33.9%), 4380 (29.3%), 1956 (13.1%) and 1510 (10.1%) patients had no (eRVSP<30.00 mm Hg), borderline (30.00-39.99 mm Hg), mild (40.00-49.99 mm Hg), moderate (50.00-59.99 mm Hg) and severe PHT (>60.00 mm Hg), respectively. An echocardiographic phenotype was evident with worsening PHT, showing rising E:e' ratio and right and left atrial sizes(p<0.0001, for all). Adjusted analyses showed that the risk of long-term mortality progressively rose as eRVSP level increased (HR 1.14-2.94, borderline to severe PHT, p<0.0001 for all). A mortality threshold was identified in the 4th decile of eRVSP categories (35.01-38.00 mm Hg; HR 1.19, 95% CI 1.04 to 1.35), with risk progressively increasing through to the 10th decile (HR 2.86, 95% CI 2.54 to 3.21).

CONCLUSIONS

In this large cohort study, we find that PHT is common in ≥moderate AS and mortality increases as PHT becomes more severe. A threshold for higher mortality lies within the range of 'borderline-mild' PHT.

TRIAL REGISTRATION NUMBER

ACTRN12617001387314.

Acute heart failure and valvular heart disease: A scientific statement of the Heart Failure Association, the Association for Acute CardioVascular Care and the European Association of Percutaneous Cardiovascular Interventions of the European Society of Cardiology

Acute heart failure (AHF) represents a broad spectrum of disease states, resulting from the interaction between an acute precipitant and a patient's underlying cardiac substrate and comorbidities. Valvular heart disease (VHD) is frequently associated with AHF. AHF may result from several precipitants that add an acute haemodynamic stress superimposed on a chronic valvular lesion or may occur as a consequence of a new significant valvular lesion. Regardless of the mechanism, clinical presentation may vary from acute decompensated heart failure to cardiogenic shock. Assessing the severity of VHD as well as the correlation between VHD severity and symptoms may be difficult in patients with AHF because of the rapid variation in loading conditions, concomitant destabilization of the associated comorbidities and the presence of combined valvular lesions. Evidence-based interventions targeting VHD in settings of AHF have yet to be identified, as patients with severe VHD are often excluded from randomized trials in AHF, so results from these trials do not generalize to those with VHD. Furthermore, there are not rigorously conducted randomized controlled trials in the setting of VHD and AHF, most of the data coming from observational studies. Thus, distinct to chronic settings, current guidelines are very elusive when patients with severe VHD present with AHF, and a clear-cut strategy could not be yet defined. Given the paucity of evidence in this subset of AHF patients, the aim of this scientific statement is to describe the epidemiology, pathophysiology, and overall treatment approach for patients with VHD who present with AHF.

Impact of Pulmonary Hypertension on Mortality after Surgery for Aortic Stenosis

Background and Objectives: The prognosis of patients with aortic stenosis (AS) adding pulmonary hypertension (PHT) is worse than in those with normal pulmonary artery pressure (PAP), and there are few results reported for the association between PHT and adverse outcomes of AS. We aimed to determine the predictive factors for the development of PHT in patients with surgical AS and to identify those factors that may predict the surgical prognosis. We aimed to identify the independent predictors for PHT regression at 2 years after surgery. Additionally, we tried to evaluate the involvement of PHT as an additional perioperative risk factor in patients with AS undergoing surgical aortic valve replacement (AVR). Materials and Methods: We carried out a two-year prospective study on 340 patients with AS undergoing surgical AVR. Results: The independent predictors for the occurrence of PHT in patients with surgical AS were: age > 75 years (RR = 6, p = 0.001), a restrictive left ventricle diastolic filling pattern (LVDFP) (RR = 9, p = 0.001) and associated moderate mitral regurgitation (MR) (RR = 9, p = 0.0001). The presence of severe PHT increased by 7.6 times the early postoperative risk of death, regardless of the presence of other parameters. The independent predictors for early postoperative mortality were: severe PHT, restrictive left ventricle diastolic pattern, age > 75 years, interventricular septum (IVS) thickness >18 mm and the presence of comorbidities. Conclusions: The presence of a severe PHT in patients with AS undergoing surgical AVR is associated with an early postoperative increased mortality rate. The mean PAP is a more reliable parameter for prognosis appreciation than the LV systolic function.

Determinants of changes in pulmonary artery pressure in patients with severe aortic stenosis treated by transcatheter aortic valve implantation

BACKGROUND

Elevated pulmonary artery pressure (PAP) in patients with severe aortic stenosis (AS) is a strong predictor of adverse prognosis. This study sought to assess the relation between PAP and clinical and echocardiographic parameters in elderly patients with severe AS, as well as to identify the determinants of the change in PAP after transcatheter aortic valve implantation (TAVI).

METHODS

The study included 170 subjects (age 81 ± 7 years, 45% men) with symptomatic severe AS who were treated by TAVI. They underwent a clinical evaluation and a transthoracic echocardiography before the TAVI procedure and 6 months after.

RESULTS

In a multivariable analysis, the independent predictors for baseline PAP were the body mass index (BMI) (β = 0.21, p = .006), COPD GOLD class (β = 0.20; p = .009), the E/e' ratio (β = 0.20; p = .02) and the degree of aortic regurgitation (β = 0.20; p = .01). After TAVI, there was significantly less (51% vs. 29%, p<.0001) pulmonary hypertension, defined as a tricuspid regurgitation velocity ≥2.8 m/s. The baseline variables related to an improvement in PAP were the tricuspid regurgitation velocity (p = .0001) and the E/e' (p = .005). From the parameters potentially modified with TAVI, the only independent predictor of PAP variation was the change in the E/e' ratio (β = 0.23; p = .01).

CONCLUSIONS

Independent predictors for baseline PAP in elderly patients with symptomatic AS were the BMI, GOLD class, the aortic regurgitation and the E/e' ratio. The baseline predictors for a change in PAP 6 months after TAVI were the baseline PAP and E/e', with only the change in the E/e' ratio being correlated to the change in PAP.

Practice patterns of pulmonary hypertension secondary to left heart disease among pediatric pulmonary hypertension providers

Development of pulmonary hypertension (PH) in patients with left side heart disease (LHD) is a predictor of poor prognosis. The use of pulmonary vasodilators in PH associated with LHD (PH-LHD) is controversial. In this study, we describe the practice patterns regarding the use of pulmonary vasodilators in PH-LHD among a group of international pediatric PH specialists. A survey was distributed to the members of three pediatric PH networks: PPHNet, PVRI, and REHIPED. The survey queried participants on the rationale, indications, and contraindications of the use of pulmonary vasodilators in children with PH-LHD. Forty-seven PH specialists from 39 PH centers completed the survey. Participants included PH specialists from North America (57%), South America (15%), and Europe (19%). The majority of participants (74%) recommended the use of pulmonary vasodilators only in patients with combined pre-capillary and post-capillary pulmonary hypertension. Participants required the presence of clinical symptoms or signs of heart failure (68%) or right ventricular dysfunction by echocardiography (51%) in order to recommend pulmonary vasodilator therapy. There was no agreement regarding hemodynamic criteria used to recommend pulmonary vasodilators or the etiologies of LHD considered contraindications for using pulmonary vasodilators to manage PH-LHD. Of the available PH-targeted drugs, most participants preferred the use of phosphodiesterase-5-inhibitors for this indication. In conclusion, the practice of recommending pulmonary vasodilators in PH-LHD is highly variable among international pediatric PH specialists. Most specialists of those surveyed (57% in North America) would consider the use of pulmonary vasodilators in PH-LHD only if pre-capillary pulmonary hypertension and right ventricular dysfunction are present.

The Outcomes of Pulmonary Hypertension Patients With Severe Aortic Stenosis Who Underwent Surgical Aortic Valve Replacement or Transcatheter Aortic Valve Implantation

The outcomes for patients who undergo transcatheter aortic valve implantation (TAVI) and surgical aortic valve replacement (SAVR) with pulmonary hypertension (PH) is not well understood. We sought to evaluate the outcomes of patients with PH who underwent TAVI compared with SAVR. We identified patients who were diagnosed with PH and underwent TAVI SAVR for aortic valve stenosis in the National Inpatient Sample database who were admitted from 2011 to 2014. Propensity score matching was used to generate 2 matched cohorts for TAVI and SAVR and outcomes were compared using logistic regressions. A total of 36,786 patients were diagnosed with PH and had an intervention for aortic valve stenosis. Twenty six percent underwent TAVI (n = 9,560) and 74% underwent SAVR (n = 27,225). Patients in the TAVI group were older (81.0 vs 68.5, p <0.001) had more women (53.2% vs 45.4%) and less African-American patients (4.6% vs 8.3%; p <0.001 for both). Although both groups had comparable co-morbidities, the TAVI group had higher prevalence of congestive heart failure, chronic pulmonary disease, renal failure, peripheral vascular disease, coronary artery disease, and previous stroke compared with the SAVR group (p ≤0.002). After propensity-score-matching, patients with PH had no statistically significant difference in in-hospital mortality between for TAVI or SAVR procedures (5.6% vs 4.6%, odds ratio [OR] 1.23, confidence interval [CI] 0.92 to 1.66, p = 0.165). However, TAVI patients were less likely to have cardiac complications (15.4% vs 19.9%, OR 0.73, CI 0.61 to 0.87, p = 0.001) and respiratory complications (12.4% vs 25.1%, OR 0.42, CI 0.35 to 0.51, p <0.001). In conclusion, whereas patient with PH who underwent TAVI and SAVR had similar in-hospital mortality, TAVI was associated with lower cardiac, respiratory and bleeding complications compared with SAVR.

Characterization of biventricular alterations in myocardial (reverse) remodelling in aortic banding-induced chronic pressure overload

Aortic Stenosis (AS) is the most frequent valvulopathy in the western world. Traditionally aortic valve replacement (AVR) has been recommended immediately after the onset of heart failure (HF) symptoms. However, recent evidence suggests that AVR outcome can be improved if performed earlier. After AVR, the process of left ventricle (LV) reverse remodelling (RR) is variable and frequently incomplete. In this study, we aimed at detecting mechanism underlying the process of LV RR regarding myocardial structural, functional and molecular changes before the onset of HF symptoms. Wistar-Han rats were subjected to 7-weeks of ascending aortic-banding followed by a 2-week period of debanding to resemble AS-induced LV remodelling and the early events of AVR-induced RR, respectively. This resulted in 3 groups: Sham (n = 10), Banding (Ba, n = 15) and Debanding (Deb, n = 10). Concentric hypertrophy and diastolic dysfunction (DD) were patent in the Ba group. Aortic-debanding induced RR, which promoted LV functional recovery, while cardiac structure did not normalise. Cardiac parameters of RV dysfunction, assessed by echocardiography and at the cardiomyocyte level prevailed altered after debanding. After debanding, these alterations were accompanied by persistent changes in pathways associated to myocardial hypertrophy, fibrosis and LV inflammation. Aortic banding induced pulmonary arterial wall thickness to increase and correlates negatively with effort intolerance and positively with E/e′ and left atrial area. We described dysregulated pathways in LV and RV remodelling and RR after AVR. Importantly we showed important RV-side effects of aortic constriction, highlighting the impact that LV-reverse remodelling has on both ventricles.

Pulmonary Hypertension in Aortic and Mitral Valve Disease

In patients with aortic and/or mitral valve disease the presence of pulmonary hypertension (PH) indicates a decompensated state of the disease with left ventricular and left atrial dysfunction and exhausted compensatory mechanism, i.e., a state of heart failure. Pulmonary hypertension in this context is the consequence of the backwards transmission of elevated left atrial pressure. In this form of PH, pulmonary vascular resistance is initially normal (isolated post-capillary PH). Depending on the extent and chronicity of left atrial pressure elevation additional pulmonary vascular remodeling may occur (combined pre- and post-capillary PH). Mechanical interventions for the correction of valve disease often but not always reduce pulmonary pressures. However, the reduction in pulmonary pressures is often modest, and persistent PH in these patients is common and a marker of poor prognosis. In the present review we discuss the pathophysiology and clinical impact of PH in patients with aortic and mitral valve disease, the comprehensive non-invasive and invasive diagnostic approach required to define treatment of PH, and recent insights from mechanistic studies, registries and randomized studies, and we provide an outlook regarding gaps in evidence, future clinical challenges, and research opportunities in this setting.

Left atrial dysfunction as a determinant of pulmonary hypertension in patients with severe aortic stenosis and preserved left ventricular ejection fraction

In patients with severe aortic stenosis (AS), the presence of pulmonary hypertension (PH) has been linked to a poor prognosis. We aimed to assess the main determinants of PH in patients with severe AS and preserved left ventricular ejection fraction (LVEF). We prospectively enrolled 108 consecutive patients with isolated severe AS (indexed aortic valve area <0.6 cm²/m²) and LVEF >50%, in sinus rhythm. Left atrial (LA) function was assessed using longitudinal deformation parameters (by speckle tracking echocardiography). PH (defined as systolic pulmonary artery pressure >40 mmHg) was present in 20 patients. Patients with severe AS and PH were older (p = 0.05), had higher BNP values (p = 0.05) and a greater degree of LV diastolic dysfunction: higher E/e' and E/A ratios and lower EDT values (p < 0.03 for all) compared to patients without PH. There were no differences between groups regarding AS severity and LV systolic function parameters. Patients with PH had a more impaired LA function: lower septal and lateral late diastolic peak velocity a' (p < 0.001 and p = 0.04 respectively) and lower LA peak longitudinal strain and strain rate parameters (p ≤ 0.005 for all). In multivariable analysis, LA late diastolic longitudinal strain rate was the only independent correlate of PH in our patients (p = 0.04). Patients with isolated severe AS, preserved LVEF and PH had larger LA volumes, a more impaired LA function, and higher LV filling pressures compared to those without PH. LA booster pump function, reflected by late diastolic longitudinal strain rate, emerged as an independent correlate of PH in these patients.

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.

Prognostic Impact of Tricuspid Regurgitation in Patients Undergoing Aortic Valve Surgery for Aortic Stenosis

BACKGROUND

The prognostic significance of tricuspid regurgitation (TR) and right ventricular (RV) function in patients undergoing aortic valve replacement (AVR) for severe aortic stenosis (AS) is unknown. The aim of the present study was to evaluate the impact of TR and RV systolic dysfunction on early and late mortality in this setting.

METHODS

This was a prospective single-center observational study. 465 consecutive patients who were referred to AVR for severe AS were investigated. Significant TR was defined as TR≥moderate by transthoracic echocardiography.

RESULTS

At baseline, significant TR was present in 26 (5.6%) patients. Patients with TR presented with a higher EuroSCORE I (p = 0.001), a higher incidence of previous cardiac surgery (p<0.001), pulmonary hypertension (p = 0.003), more dilated RVs (p = 0.001), and more frequent RV dysfunction (p = 0.001). Patients were followed for an average of 5.2 (±2.8 SD) years. By multivariable Cox regression analysis TR (p = 0.014), RV dysfunction (p = 0.046), age (p = 0.001) and concomitant coronary artery bypass graft surgery (CABG, p = 0.003) were independently associated with overall mortality. By Kaplan-Meier analysis, survival rates were significantly worse in patients with significant than with non-significant TR (log rank p = 0.001).

CONCLUSIONS

TR, RV dysfunction, age, and concomitant CABG are associated with outcome in patients undergoing AVR for severe AS. This finding underlines the importance of a thorough echocardiographic evaluation with particular consideration of the right heart in these patients.

Prevalence and impact of pulmonary hypertension on patients with aortic stenosis who underwent transcatheter aortic valve replacement

Limited amount of data suggest that patients with aortic stenosis and pulmonary hypertension (PH) who undergo transcatheter aortic valve replacement (TAVR) experience decrease in PH postprocedure. Inconsistent use of systolic pulmonary artery pressure cut-off values in previous studies limits our ability to draw meaningful conclusions regarding the prognostic role of PH in assessment of TAVR candidates. A total of 415 consecutive patients who underwent TAVR were included in the present study. Two groups were compared based on receiver-operating characteristics curve analysis for the best SPAP value to predict outcome, yielding 2 study groups of no/mild PH (≤50 mm Hg; n = 172, 41%) versus moderate/severe PH (>50 mm Hg; n = 243, 59%). Demographics and co-morbidities were comparable between the 2 groups; however, right-sided cardiac failure (35% vs 19.8%, p = 0.02) and mitral regurgitation (18.4% vs 8.6%, p = 0.007) were more frequent in patients with moderate/severe PH. Procedural characteristics and complications were comparable between the groups. Although there was an early overall decrease in SPAP postprocedure, only 26% of moderate/severe patients with PH experienced a significant decrease in SPAP (>10 mm Hg). The 30-day (14.5% vs 7.4%, p = 0.02) and 1-year mortality (30.8% vs 21%, p = 0.02) was higher in moderate/severe patients with PH. In multivariate analysis, systolic pulmonary artery pressure and chronic lung disease were identified as independent predictors for mortality at 1 year. PH is a frequent co-morbidity in patients with severe aortic stenosis who underwent TAVR. Significantly elevated pulmonary artery pressures at baseline may serve as a poor prognostic factor when performing preprocedural assessment of the patients.

Prognostic impact of pulmonary artery systolic pressure in patients undergoing transcatheter aortic valve replacement for aortic stenosis

Baseline pulmonary hypertension (PH) is a predictor of poor outcomes in patients with severe aortic stenosis (AS). Surgical aortic valve replacement is thought to alleviate PH. The aim of this study was to determine the prognostic impact of PH in patients who underwent transcatheter aortic valve replacement (TAVR). An observational cohort study was conducted using prospectively collected data on 277 consecutive patients with severe AS who underwent TAVR at the Mayo Clinic (Rochester, Minnesota) from November 1, 2008, to June 31, 2013. Clinical and echocardiographic data, pulmonary function characteristics, and outcomes stratified by tertiles of pulmonary artery systolic pressure (PASP) were analyzed. From 277 patients who underwent TAVR, 251 patients had PASP assessment at baseline. Those in the highest PASP tertile (PASP ≥49 mm Hg) had more severe chronic lung disease and worse diastolic dysfunction. Being in the highest PASP tertile was an independent predictor of long-term mortality (hazard ratio 2.88, 95% confidence interval 1.15 to 7.23). Patients in the highest PASP tertile had longer lengths of hospital stay, while other short-term outcomes (30-day mortality and readmission, stroke, prolonged ventilation, and reoperation for bleeding) were similar across PASP tertiles. TAVR was associated with a decrease in PASP in the highest PASP tertile at 1 week after the procedure (-8 ± 14 mm Hg) and at 3 months (-7 ± 15 mm Hg) compared with baseline. In conclusion, among patients with severe AS who underwent TAVR, higher baseline PASP was strongly associated with diastolic dysfunction and chronic lung disease. Patients with higher baseline PASP tolerated TAVR relatively well in the early postprocedural phase, with diminished long-term survival. PH should not disqualify patients with severe AS from consideration for TAVR.

Severe aortic stenosis: forgotten associations

The authors present the case of a 68-year-old man with predominantly right heart failure in the context of severe aortic stenosis associated with pulmonary hypertension. Anemia was diagnosed which, after endoscopic study, was considered to be secondary to angiodysplasia and a diagnosis of Heyde syndrome was made. After valve replacement surgery the patient's heart failure improved and hemoglobin levels stabilized. We present this case to show the need to recognize less common associations of severe aortic stenosis, in order to provide immediate and appropriate treatment.

Predictors of hospitalisations for heart failure and mortality in patients with pulmonary hypertension associated with left heart disease: a systematic review

OBJECTIVES

Left heart disease (LHD) is the main cause of pulmonary hypertension (PH), but little is known regarding the predictors of adverse outcome of PH associated with LHD (PH-LHD). We conducted a systematic review to investigate the predictors of hospitalisations for heart failure and mortality in patients with PH-LHD.

DESIGN

Systematic review.

DATA SOURCES

PubMed MEDLINE and SCOPUS from inception to August 2013 were searched, and citations identified via the ISI Web of Science.

STUDY SELECTION

Studies that reported on hospitalisation and/or mortality in patients with PH-LHD were included if the age of participants was greater than 18 years and PH was diagnosed using Doppler echocardiography and/or right heart catheterisation. Two reviewers independently selected studies, assessed their quality and extracted relevant data.

RESULTS

In all, 45 studies (38 from Europe and USA) were included among which 71.1% were of high quality. 39 studies were published between 2003 and 2013. The number of participants across studies ranged from 46 to 2385; the proportion of men from 21% to 91%; mean/median age from 63 to 82 years; and prevalence of PH from 7% to 83.3%. PH was consistently associated with increased mortality risk in all forms of LHD, except for aortic valve disease where findings were inconsistent. Six of the nine studies with data available on hospitalisations reported a significant adverse effect of PH on hospitalisation risk. Other predictors of adverse outcome were very broad and heterogeneous including right ventricular dysfunction, functional class, left ventricular function and presence of kidney disease.

CONCLUSIONS

PH is almost invariably associated with increased mortality risk in patients with LHD. However, effects on hospitalisation risk are yet to be fully characterised; while available evidence on the adverse effects of PH have been derived essentially from Caucasians.

Update on cardiac imaging techniques 2012

Cardiac imaging is one of the basic pillars of modern cardiology. The potential list of scenarios where cardiac imaging techniques can provide relevant information is simply endless so it is impossible to include all relevant new features of cardiac imaging published in the literature in 2012 in the limited format of a single article. We summarize the year's most relevant news on cardiac imaging, highlighting the ongoing development of myocardial deformation and 3-dimensional echocardiography techniques and the increasing use of magnetic resonance imaging and computed tomography in daily clinical practice.

WHO's in second?: A practical review of World Health Organization group 2 pulmonary hypertension

World Health Organization (WHO) group 2 pulmonary hypertension (PH) due to left-side heart disease (ie, heart failure or left-sided valvular heart disease) is the most common form of PH in western countries. Distinguishing patients with WHO group 2 PH, particularly the subset of patients with PH due to heart failure with preserved ejection fraction (HFpEF), from those with WHO group 1 pulmonary arterial hypertension (PAH) is challenging. Separating the two conditions is of vital importance because treatment strategies differ completely. Furthermore, therapies that are indicated for WHO group 1 PAH may be harmful in patients with WHO group 2 PH. We review the somewhat confusing PH nomenclature and the WHO classification system and rationale behind it. We then focus on left-side heart disorders that cause PH. An aging population and advances in the medical management of common cardiovascular disorders have caused the prevalence of heart failure to rise significantly, with more than one-half of patients having HFpEF. We review contemporary studies that focus on clinical and echocardiographic findings that help to distinguish HFpEF from PAH in the patient with PH. We discuss the typical, and sometimes atypical, hemodynamic profiles that characterize these two groups, review challenges in the interpretation of data obtained by right-sided heart catheterization, and highlight special maneuvers that may be required for accurate diagnosis. Finally, we review the largely disappointing studies on the use of PAH-specific therapies in patients with WHO group 2 PH, including the use of prostacyclins, endothelin receptor antagonists, and the more promising phosphodiesterase-5 inhibitors.

Effect of preoperative pulmonary hypertension on outcomes in patients with severe aortic stenosis following surgical aortic valve replacement

Pulmonary hypertension (PH) is prevalent in patients with aortic stenosis (AS); however, previous studies have demonstrated inconsistent results regarding the association of PH with adverse outcomes after aortic valve replacement (AVR). The goal of this study was to evaluate the effects of preoperative PH on outcomes after AVR. We performed a regional prospective cohort study using the Northern New England Cardiovascular Disease Study Group database to identify 1,116 consecutive patients from 2005 to 2010 who underwent AVR ± coronary artery bypass grafting for severe AS with a preoperative assessment of pulmonary pressures by right-sided cardiac catheterization. PH was defined as a mean pulmonary artery pressure of ≥25 mm Hg, with severity based on the pulmonary artery systolic pressure-mild, 35 to 44 mm Hg; moderate, 45 to 59 mm Hg; and severe, ≥60 mm Hg. We found that PH was present in 536 patients (48%). Postoperative acute kidney injury, low-output heart failure, and in-hospital mortality increased with worsening severity of PH. In multivariate logistic regression, severe PH was independently associated with postoperative acute kidney injury (adjusted odds ratio 4.1, 95% confidence interval [CI] 1.7 to 10, p = 0.002) and in-hospital mortality (adjusted odds ratio 6.9, 95% CI 2.5 to 19.1, p <0.001). There was a significant association between PH and decreased 5-year survival (adjusted log-rank p value = 0.006), with severe PH being associated with the poorest survival (adjusted hazard ratio 2.4, 95% CI 1.3 to 4.2, p = 0.003). In conclusion, severe PH in patients with severe AS is associated with increased rates of in-hospital adverse events and decreased 5-year survival after AVR.

Assessment of cardiovascular function by combining clinical data with a computational model of the cardiovascular system

OBJECTIVE

A sufficient understanding of patients' cardiovascular status is necessary for doctors to make the best decisions with regard to the treatment of cardiovascular disease; however, it is often not available because of the limitation of clinical measurements. The objective of this study was to examine whether cardiovascular function can be assessed quantitatively and for specific patients by combining clinical data with a computational model of the cardiovascular system.

METHODS

Seven consecutive patients undergoing off-pump coronary artery bypass grafting were enrolled in this study. The clinical data were collected both during the preoperative diagnosis and during the operation. Sensitivity analysis was performed to select the major model parameters most relevant to the measured data. The major model parameters were then estimated through a data-fitting procedure, enabling a patient-specific quantitative assessment of various aspects of cardiovascular function.

RESULTS

The results revealed the prevalence of left ventricular diastolic dysfunction in the patients, although the severity of dysfunction exhibits significant interpatient variability (the estimated left ventricular passive elastance varies from 194% to 540% of its reference value). Moreover, 4 of the 7 patients studied had impaired left ventricular systolic function.

CONCLUSIONS

The current study demonstrates the feasibility of assessing cardiovascular function quantitatively by combining clinical data with a cardiovascular model. In particular, the assessment utilizes the measurements already in use or available in clinical settings, enhancing the clinical potential of the proposed method.

Determinants and prognostic significance of exercise pulmonary hypertension in asymptomatic severe aortic stenosis

BACKGROUND

Recent studies emphasized the usefulness of exercise stress echocardiography in asymptomatic patients with aortic stenosis. Nevertheless, the additive value of exercise pulmonary hypertension (Ex-PHT) in such patients remains unexplored. We therefore aimed to identify the determinants and to test the impact on outcome of Ex-PHT in asymptomatic patients with severe aortic stenosis.

METHOD AND RESULTS

Asymptomatic patients with severe aortic stenosis (n=105; aortic valve area <0.6 cm(2)/m(2); age, 71±9 years; male, 59%) and preserved left ventricular systolic function (ejection fraction ≥55%) were prospectively submitted to exercise stress echocardiography. Resting PHT and Ex-PHT were defined as a systolic pulmonary arterial pressure >50 and >60 mm Hg, respectively. Ex-PHT was more frequent than resting PHT (55% versus 6%; P<0.0001). On multivariable logistic regression, the independent predictors of Ex-PHT were male sex (odds ratio, 4.3; P=0.002), resting systolic pulmonary arterial pressure (odds ratio, 1.16; P=0.002), exercise indexed left ventricular end-diastolic volume (odds ratio, 1.04; P=0.026), exercise e'-wave velocity (odds ratio, 1.35; P=0.047), and exercise-induced changes in indexed left atrial area (odds ratio, 1.36; P=0.006). Ex-PHT was associated with reduced cardiac event-free survival (at 3 years, 22±7% versus 55±9%; P=0.014). In a multivariable Cox proportional hazards model, Ex-PHT was identified as an independent predictor of cardiac events (hazard ratio, 1.8; 95% confidence interval, 1.0-3.3; P=0.047). When exercise-induced changes in mean aortic pressure gradient were added to the multivariable model, Ex-PHT remained independently associated with reduced cardiac event-free survival (hazard ratio, 2.0; 95% confidence interval, 1.1-3.6; P=0.025).

CONCLUSIONS

In asymptomatic patients with severe aortic stenosis, the main determinants of Ex-PHT are male sex, resting systolic pulmonary arterial pressure, and exercise parameters of diastolic burden. Moreover, Ex-PHT is associated with a 2-fold increased risk of cardiac events. These results strongly support the use of exercise stress echocardiography in asymptomatic aortic stenosis.

The year in review: the surgical treatment of valvular disease-2011

This review highlights important advances in techniques, guidelines, outcomes and innovations in valve surgery during 2011.