Paradoxical Septal Motion after Uncomplicated Cardiac Surgery: A Consequence of Altered Regional Right Ventricular Contractile Patterns

Paroxysmal interventricular septal motion (PSM) is the movement of the septum toward the right ventricle (RV) during cardiac systole. It occurs frequently after uncomplicated cardiac surgery (CS), including coronary bypass (on-pump and off-pump), valve repair or replacement, and with all types of incisions (sternotomy or mini-thoracotomy). It sometimes resolves quickly but may persist for months or become permanent. Global RV systolic function, stroke volume and ejection fraction remain normal after uncomplicated CS, but regional contractile patterns are altered. There is a decrease in longitudinal shortening but an increase in transverse shortening in the endocardial and epicardial right ventricular muscle fibers, respectively. PSM is a secondary event as there is no loss of septal perfusion or thickening. The increased RV transverse shortening (free wall to septal fibers) may modify septal movement resulting in PSM that compensates for the reduced RV longitudinal shortening, thus preserving normal global right ventricular function.

Long-term assessment of clinical outcomes and disease progression in patients with corrected Tetralogy of Fallot

OBJECTIVE

Understanding changes of right ventricular (RV) geometry and function in repaired Tetralogy of Fallot (rToF) patients can improve decision-making for pulmonary valve replacement. Therefore, we aimed to assess the magnitude and clinical correlations of RV changes in rToF patients.

PATIENTS AND METHODS

Clinical and MRI data of rToF patients who underwent repeated cardiac magnetic resonance imaging (MRI) at two centers between December 2003 and September 2020 were analyzed together with anatomical factors, including RV outflow tract obstruction, pulmonary artery branch stenosis, and tricuspid regurgitation. Adverse cardiac events and/or NYHA class worsening were documented and correlated with MRI changes. QRS length was reported at each MRI.

RESULTS

Two-hundred-and-nineteen rToF patients (53% males, aged 20.2 ± 10.1 years) were enrolled. An increase of ventricular dimensions, except LVEDVi, and worsening of right and left ejection fractions were found over an average period of 5 years of follow-up. These changes were statistically significant but within 10% of the initial value. No significant changes were reported on a year-to-year basis, except in a small group of patients (6%) in whom no predictive factors were identified. Despite similar RV dimensions at the first examination, younger patients had a higher RV ejection fraction and a different annual rate of change of ventricular dimensions compared to older ones. Patients with arrhythmias (20%) were more frequently older and had larger RV dimensions but showed no significant correlations with MRI changes/years.

CONCLUSIONS

 Changes in RV dimensions and function occur rarely and very slowly in rToF patients. A small percentage of patients experience a significant worsening in a short time interval without any recognized risk factors. Arrhythmias appear to occur in a small percentage of cases in the late follow-up.

Right ventricular function and vasoactive peptides for early prediction of bronchopulmonary dysplasia

BACKGROUND

To assess the prognostic value of early echocardiographic indices of right ventricular function and vasoactive peptides for prediction of bronchopulmonary dysplasia (BPD) or death in very preterm infants.

METHODS

Prospective study involving 294 very preterm infants (median [IQR] gestational age 28.4 [26.4-30.4] weeks, birth weight 1065 [800-1380] g), of whom 57 developed BPD (oxygen supplementation at 36 weeks postmenstrual age) and 10 died. Tricuspid annular plane systolic excursion (TAPSE), right ventricular index of myocardial performance (RIMP), plasma concentrations of mid-regional pro-atrial natriuretic peptide (MR-proANP) and C-terminal pro-endothelin-1 (CT-proET1) were measured on day 7 of life.

RESULTS

RIMP was significantly increased (median [IQR] 0.3 [0.23-0.38] vs 0.22 [0.15-0.29]), TAPSE decreased (median [IQR] 5.0 [5.0-6.0] vs 6.0 [5.4-7.0] mm), MR-proANP increased (median [IQR] 784 [540-936] vs 353 [247-625] pmol/L), and CT-proET1 increased (median [IQR] 249 [190-345] vs 199 [158-284] pmol/L) in infants who developed BPD or died, as compared to controls. All variables showed significant but weak correlations with each other (rS -0.182 to 0.359) and predicted BPD/death with similar accuracy (areas under receiver operator characteristic curves 0.62 to 0.77). Multiple regression revealed only RIMP and birth weight as independent predictors of BPD or death.

CONCLUSIONS

Vasoactive peptide concentrations and echocardiographic assessment employing standardized measures, notably RIMP, on day 7 of life are useful to identify preterm infants at increased risk for BPD or death.

Normative Echocardiographic Values for Right and Left Ventricular Function in Extremely Premature Neonates

OBJECTIVE

To identify the measures of biventricular function and surrogates of pulmonary vascular resistance that can be expected in relatively stable extremely premature neonates, and evaluate maturational changes in myocardial performance in this patient population.

STUDY DESIGN

This was a prospective observational study. Clinically stable extremely preterm newborns were divided into 3 cohorts based on gestational age: cohort 1 (24^0/7-25^6/7 weeks), cohort 2 (26^0/7-27^6/7 weeks), and cohort 3 (28^0/7-29^6/7 weeks). Serial echocardiograms were obtained on day of life 3-5, 7-10, and just prior to discharge.

RESULTS

In total, 46 subjects met the criteria aimed at capturing only the most clinically healthy and stable newborns less than 29^6/7 weeks of gestational age. Myocardial performance was reliably assessed by echocardiography with high inter-reader correlation. Normative values were identified for right ventricular function, left ventricular function, and surrogates of pulmonary vascular resistance.

CONCLUSIONS

Biventricular systolic performance is significantly different in the clinically stable extremely premature neonate when compared with healthy full-term newborns. All participants had evidence of poor biventricular compliance at birth which improved with maturation. Extreme prematurity does not appear to adversely affect myocardial functional maturation at the time of term corrected age and/or discharge.

Outcomes and Echocardiographic Follow-up After Surgical Management of Tricuspid Regurgitation in Patients With Transvenous Right Ventricular Leads

OBJECTIVE

To evaluate outcomes of elective surgical management of tricuspid regurgitation (TR) in patients with transvenous right ventricular leads, and compare results between non-lead-induced and lead-induced TR patients.

PATIENTS AND METHODS

We studied patients with right ventricular leads who underwent tricuspid valve surgery from January 1, 1993, through December 31, 2015, and categorized them as non-lead-induced and lead-induced TR. Propensity score (PS) for the tendency to have lead-induced TR was estimated from logistic regression and was used to adjust for group differences.

RESULTS

From the initial cohort of 470 patients, 444 were included in PS-adjustment analyses (174 non-lead-induced TRs [123 repairs, 51 replacements], 270 lead-induced TRs [129 repairs, 141 replacements]). In PS-adjusted multivariable analysis, lead-induced TR was not associated with mortality (P=.73), but tricuspid valve replacement was (hazard ratio, 1.59; 95% CI, 1.13 to 2.25; P=.008). Five-year freedom from tricuspid valve re-intervention was 100% for non-lead-induced TR and 92.3% for lead-induced TR; rates adjusted for PS differed between groups (P=.005). There was significant improvement in TR postoperatively in each group (P<.001). In patients having tricuspid valve repair, TR grades tended to worsen over time, but the difference in trends was not significantly different between groups.

CONCLUSION

Lead-induced TR did not affect long-term survival after elective tricuspid valve surgery. In patients with lead-induced TR, tricuspid valve re-intervention was more common. Improvement in TR was achieved in both groups after surgery; however, severity of TR tended to increase over follow-up after tricuspid valve repair.

Long-term survival in patients with post-LVAD right ventricular failure: multi-state modelling with competing outcomes of heart transplant

BACKGROUND

Multicenter data on long term survival following LVAD implantation that make use of contemporary definitions of RV failure are limited. Furthermore, traditional survival analyses censor patients who receive a bridge to heart transplant. Here we compare the outcomes of LVAD patients who develop post-operative RV failure accounting for the transitional probability of receiving an interim heart transplantation.

METHODS

We use a retrospective cohort of LVAD patients sourced from multiple high-volume centers based in the United States. Five- and ten-year survival accounting for transition probabilities of receiving a heart transplant were calculated using a multi-state Aalen Johansen survival model.

RESULTS

Of the 897 patients included in the study, 238 (26.5%) developed post-operative RV failure at index hospitalization. At 10 years the probability of death with post-op RV failure was 79.28% vs 61.70% in patients without (HR 2.10; 95% CI 1.72 - 2.57; p = < .001). Though not significant, patients with RV failure were less likely to be bridged to a heart transplant (HR 0.87, p = .4). Once transplanted the risk of death between both patient groups remained equivalent; the probability of death after a heart transplant was 3.97% in those with post-operative RV failure shortly after index LVAD implant, as compared to 14.71% in those without.

CONCLUSIONS AND RELEVANCE

Long-term durable mechanical circulatory support is associated with significantly higher mortality in patients who develop post-operative RV failure. Improving outcomes may necessitate expeditious bridge to heart transplant wherever appropriate, along with critical reassessment of organ allocation policies.

Right ventricular contractility decreases during exercise in patients with non-advanced idiopathic pulmonary fibrosis

Early right ventricular dysfunction in patients with non-advanced idiopathic pulmonary fibrosis (IPF) has not been fully elucidated. Thus, we aimed to assess right ventricular functions in IPF patients and controls by speckle-tracking strain echocardiography at rest and peak exercise.We screened 116 IPF patients from February to August 2019 to include 20 patients with no history of oxygen therapy, peripheral saturation levels ≥92% at rest, Gender-Age-Physiology Index score ≤5, and modified Medical Research Council score ≤3. Additionally, we enrolled 10 matched controls. Transthoracic echocardiography images were acquired at rest and during a cardiopulmonary exercise test. We analyzed 2-dimensional echocardiographic parameters and right ventricular function using the global longitudinal strain assessed by the 2-dimensional speckle-tracking technique.In the control group, we found normal values of right ventricle longitudinal strain (RVLS) at rest and at peak exercise, the latter being much more negative (-23.6 ± 2.2% and -26.8 ± 3.1%, respectively; P < .001). By contrast, RVLS values in the IPF group increased from -21.1 ± 3.8% at rest to -17.0 ± 4.5% at peak exercise (P < .001). The exercise revealed a difference between the 2 groups as the mean RVLS values moved during peak exercise in opposite directions. Patients with IPF got worse, whereas control patients presented improved right ventricular contractility.Right ventricular dysfunction was unveiled by speckle-tracking echocardiography during exercise in non-advanced IPF patients. We suggest that this reflects an inadequate right ventricular-arterial coupling decreasing the right ventricular longitudinal contraction during exercise in these patients. This parameter may be useful as an early index of suspected pulmonary hypertension.

Detrimental Immediate- and Medium-Term Clinical Effects of Right Ventricular Pacing in Patients With Myocardial Fibrosis

BACKGROUND

Long-term right ventricular (RV) pacing leads to heart failure or a decline in left ventricular (LV) function in up to a fifth of patients. We aimed to establish whether patients with focal fibrosis detected on late gadolinium enhancement cardiovascular magnetic resonance (CMR) have deterioration in LV function after RV pacing.

METHODS

We recruited 84 patients with LV ejection fraction ≥40% into 2 observational CMR studies. Patients (n=34) with a dual-chamber device and preserved atrioventricular conduction underwent CMR in 2 asynchronous pacing modes (atrial asynchronous and dual-chamber asynchronous) to compare intrinsic atrioventricular conduction with forced RV pacing. Patients (n=50) with high-grade atrioventricular block underwent CMR before and 6 months after pacemaker implantation to investigate the medium-term effects of RV pacing.

RESULTS

The key findings were (1) initiation of RV pacing in patients with fibrosis, compared with those without, was associated with greater immediate changes in both LV end-systolic volume index (5.3±3.5 versus 2.1±2.4 mL/m2; P<0.01) and LV ejection fraction (-5.7±3.4% versus -3.2±2.6%; P=0.02); (2) medium-term RV pacing in patients with fibrosis, compared with those without, was associated with greater changes in LV end-systolic volume index (8.0±10.4 versus -0.6±7.3 mL/m2; P=0.008) and LV ejection fraction (-12.3±7.9% versus -6.7±6.2%; P=0.012); (3) patients with fibrosis did not experience an improvement in quality of life, biomarkers, or functional class after pacemaker implantation; (4) after 6 months of RV pacing, 10 of 50 (20%) patients developed LV ejection fraction <35% and were eligible for upgrade to cardiac resynchronization according to current guidelines. All 10 patients had fibrosis on their preimplant baseline scan and were identified by >1.1 g of fibrosis with 90% sensitivity and 70% specificity.

CONCLUSIONS

Fibrosis detected on CMR is associated with immediate- and medium-term deterioration in LV function following RV pacing and could be used to identify those at risk of heart failure before pacemaker implantation.

Left atrial conduit function modulates right ventricular afterload, exercise capacity and survival in heart failure patients

AIMS

To assess if left atrial phasic function characteristics modulate functional capacity/survival by impacting on the pulsatile component of right ventricular (RV) afterload, as represented by pulmonary arterial compliance (PAC).

MATERIALS AND METHODS

Sixty heart failure patients (67 ± 11 years, ejection fraction 39 ± 11%, range 20--62%) underwent 6 min walk test (6MWT) and 3D transthoracic echocardiography. Left atrial conduit was computed off-line, gathering simultaneous real-time 3D multibeats (six cycles) left atrial and left ventricular (LV) volume curves, with conduit (time) = [LV (time) - LV minimum volume] - [left atrial maximum volume - left atrial (time)], expressed as % LV stroke volume. Atrial stiffness (Kla) was computed using noninvasively assessed wedge pressure divided by left atrial reservoir (maximum - minimum) volume. PAC was obtained as ratio between RV stroke volume, obtained as pulsed Doppler RV outflow tract envelope∗cross-sectional area, and pulmonary pulse pressure, obtained by transforming tricuspid regurgitant velocity in millimetres of mercury and considering diastolic pulmonary as a fixed fraction of systolic pressure.

RESULTS

Conduit averaged 34 ± 12%, PAC 3.1 ± 1.1 ml/mmHg, 6MWT 404 ± 154 m. Conduit was independent of LV volumes and ejection fraction, showing a direct dependence on noninvasive Kla (r = 0.56; P < 0.001). Dividing patients into tertiles according to 6MWT and to PAC, the largest conduit fraction was associated with the lowest functional capacity (P < 0.001) and most deranged PAC (P < 0.001), respectively, suggesting outmost RV haemodynamic burden. Tertiles of conduit predicted survival (P = 0.01).

CONCLUSION

Conduit depends on noninvasively assessed Kla and appears to be increased in heart failure patients with lowest capacity and worst survival, likely as RV pulsatile afterload, as reflected by PAC, is highest in these individuals.

Traditional and Novel Imaging of Right Ventricular Function in Patients with Heart Failure and Reduced Ejection Fraction

PURPOSE OF REVIEW

This review attempts to summarize the role of standard and advanced echocardiographic techniques together with CMR in the evaluation of the RV in HF, providing an outlook on the recent evidence.

RECENT FINDINGS

In the last decade, there has been growing interest in the study of the RV, and it is now widely established that RV function is a strong predictor of mortality, in several cardiovascular diseases, in particular in the setting of heart failure (HF). The evaluation of RV function might be particularly challenging, which justifies the necessity of multi-modality imaging. The echocardiographic assessment remains the mainstay technique even though it might be complex, due to RV crescent shape and its position in the chest, requiring both qualitative and quantitative parameters. Cardiac magnetic resonance (CMR) represents a complementary exam which is particularly useful when precise structural and functional assessment are needed, considering the most recently developed sequences. Despite the technological improvement attested over the last years, there is still no universally accepted parameter that univocally defines RV function, hence the necessity to evaluate several parameters, combining different imaging techniques.

Right-ventricular mechanics assessed by cardiovascular magnetic resonance feature tracking in children with hypertrophic cardiomyopathy

Background

Although hypertrophic cardiomyopathy (HCM) is considered a disease of the left ventricle (LV), right ventricular (RV) abnormalities have also been reported on. Cardiovascular magnetic resonance feature tracking (CMR-FT) accurately and reproducibly quantifies RV myocardial deformation.

Aim

To investigate RV deformation disorders in childhood HCM using CMR-FT.

Material and methods

Consecutive subjects aged <18 years with echocardiographic evidence of HCM were enrolled. Cardiovascular magnetic resonance (CMR) was performed including RV volumetric and functional assessment, and late gadolinium enhancement (LGE) imaging.

Results

We included 54 children (37 males, 68.5%) with HCM, of which 28 patients (51.8%; mean extent of 2.18 ± 2.34% of LV mass) had late gadolinium enhancement. LV outflow tract obstruction (LVOTO) was detected in 19 subjects (35.2%). In patients with LVOTO, RV global longitudinal strain (RVGLS) (-16.1±5.0 vs. -20.7±5.3, p<0.01), RVGLS rate (-1.05±0.30 vs. -1.26±0.40, p = 0.03), RV radial strain (RVR) (15.8±7.7 vs. 22.1±7.0, p<0.01) and RVR rate (0.95±0.35 vs. 1.6±0.44, p<0.01) were lower than in patients without LVOTO. The RVR rate (p<0.01) was lower in patients with LGE in comparison to patients without LGE.

Conclusions

Children with HCM, especially with LVOTO, have significantly reduced indices of RV mechanics despite normal RV systolic function. It seems that the degree of LVOT obstruction is responsible for compromising the RV dynamics, rather than either mass or the amount of LV fibrosis.

Preload dependence of pulmonary haemodynamics and right ventricular performance

AIMS

Systolic pulmonary artery pressure (SPAP) and right heart adaptation in relation to pre-existing preload are often disregarded. To determine volume-related changes in the pulmonary-right ventricle (RV) unit and the preload dependence of its components, we analysed pulmonary haemodynamics and right ventricular performance, taking advantage of the plasma volume removal associated to haemodialysis (HD).

METHODS AND RESULTS

Fifty-three stable patients on chronic HD with LVEF > 50% and without heart failure were recruited (mean age 63.0 ± 12.4 years; 31.2% women; hypertension in 89% and diabetes in 53%) and evaluated just before and after HD (mean ultrafiltration volume 2.4 ± 0.7 l). SPAP from both times were available in 39 patients. After HD, SPAP decreased (42.2 ± 12.6 to 33.7 ± 11.6 mmHg, p < 0.001) without modification of non-invasive pulmonary vascular resistance (1.75 ± 0.44 to 1.75 ± 0.40 eWU, p = 0.94). Age and drop in the E/e' ratio were the variables associated with greater reduction in PASP (p = 0.022 and p = 0.049, respectively). A significant reduction of right chamber sizes was observed, along with a diminution in measures of RV contractility, excluding RV longitudinal strain. Functional tricuspid regurgitation (FTR) diminution was observed in 26% of patients, occurring in every case with more than mild FTR. On multivariate analyses, left atrial size was the only predictor of pulmonary hypertension (defined as SPAP > 40 mmHg) (OR 1.29 (1.07-1.56), p = 0.006).

CONCLUSION

Rapid volemic changes may affect FTR grading, RV size and contractility, with RV longitudinal strain being less variable than conventional parameters. SPAP decreases after HD, and this reduction is related to age and greater diminution of the E/e' ratio.

Evaluation of the Systolic and Diastolic Right Ventricular Function: A Comparison Between Diabetes, Prediabetes and Normal Patients Without Coronary Artery Disease

Diabetes mellitus is a well-known dangerous factor for cardiovascular disease with high rate of comorbidities. Patients suffering from this disease have represented more heart failures which is entangled with Ischemic heart disease or high blood pressure. Thus, depending on the recent scientific facts, diabetes mellitus as a separate factor which is independent from CAD, Arterial blood pressure or other factors, is claimed to culminate in advance heart failure. Previous studies have concentrated on the impacts of diabetes and prediabetes on the performance of the left ventricular which leaves right ventricular uncovered. Consequently, the aim of this article is to analyze and compare the systolic and diastolic function of the right ventricular in normal patients and the ones with diabetes and prediabetes without any coronary artery disease.

Right Ventricular Dysfunction and Short-Term Outcomes Following Left-Sided Valvular Surgery: An Echocardiographic Study

Background The prognostic value of echocardiographic evaluation of right ventricular (RV) function in patients undergoing left-sided valvular surgery has not been well described. The objective of this study is to determine the role of broad echocardiographic assessment of RV function in predicting short-term outcomes after valvular surgery. Methods and Results Preoperative echocardiographic data, perioperative adverse outcomes, and 30-day mortality were analyzed in patients who underwent left-sided valvular surgery from 2006 to 2014. Echocardiographic parameters used to evaluate RV function include RV fractional area change, tricuspid annular plane systolic excursion, systolic movement of the RV lateral wall using tissue Doppler imaging (S'), RV myocardial performance index, and RV dP/dt. Subjects with at least 3 abnormal parameters out of the 5 aforementioned indices were defined as having significant RV dysfunction. The study included 269 patients with valvular surgery (average age: 67±15, 60.6% male, 148 aortic, and 121 mitral). RV dysfunction was found in 53 (19.7%) patients; 30-day mortality occurred in 20 patients (7.5%). Compared with normal RV function, patients with RV dysfunction had higher 30-day mortality (22.6% versus 3.8%; P=0.01) and were at risk for developing multisystem failure/shock (13.2% versus 3.2%; P=0.01). Multivariate analyses showed that preexisting RV dysfunction was the strongest predictor of increased 30-day mortality (odds ratio: 3.5; 95% CI, 1.1-11.1; P<0.05). Conclusions Preoperative RV dysfunction identified by comprehensive echocardiographic assessment is a strong predictor of adverse outcomes following left-sided valvular surgery.

Transcriptomic and Functional Analyses of Mitochondrial Dysfunction in Pressure Overload-Induced Right Ventricular Failure

Background In complex congenital heart disease patients such as those with tetralogy of Fallot, the right ventricle (RV) is subject to pressure overload, leading to RV hypertrophy and eventually RV failure. The mechanisms that promote the transition from stable RV hypertrophy to RV failure are unknown. We evaluated the role of mitochondrial bioenergetics in the development of RV failure. Methods and Results We created a murine model of RV pressure overload by pulmonary artery banding and compared with sham-operated controls. Gene expression by RNA-sequencing, oxidative stress, mitochondrial respiration, dynamics, and structure were assessed in pressure overload-induced RV failure. RV failure was characterized by decreased expression of electron transport chain genes and mitochondrial antioxidant genes (aldehyde dehydrogenase 2 and superoxide dismutase 2) and increased expression of oxidant stress markers (heme oxygenase, 4-hydroxynonenal). The activities of all electron transport chain complexes decreased with RV hypertrophy and further with RV failure (oxidative phosphorylation: sham 552.3±43.07 versus RV hypertrophy 334.3±30.65 versus RV failure 165.4±36.72 pmol/(s×mL), P<0.0001). Mitochondrial fission protein DRP1 (dynamin 1-like) trended toward an increase, while MFF (mitochondrial fission factor) decreased and fusion protein OPA1 (mitochondrial dynamin like GTPase) decreased. In contrast, transcription of electron transport chain genes increased in the left ventricle of RV failure. Conclusions Pressure overload-induced RV failure is characterized by decreased transcription and activity of electron transport chain complexes and increased oxidative stress which are associated with decreased energy generation. An improved understanding of the complex processes of energy generation could aid in developing novel therapies to mitigate mitochondrial dysfunction and delay the onset of RV failure.

Right ventricular function and cardiopulmonary performance among patients with heart failure supported by durable mechanical circulatory support devices

BACKGROUND

Patients with continuous-flow left ventricular assist devices (CF-LVADs) experience limitations in functional capacity and frequently, right ventricular (RV) dysfunction. We sought to characterize RV function in the context of global cardiopulmonary performance during exercise in this population.

METHODS

A total of 26 patients with CF-LVAD (aged 58 ± 11 years, 23 males) completed a hemodynamic assessment with either conductance catheters (Group 1, n = 13) inserted into the right ventricle to generate RV pressure‒volume loops or traditional Swan‒Ganz catheters (Group 2, n = 13) during invasive cardiopulmonary exercise testing. Hemodynamics were collected at rest, 2 sub-maximal levels of exercise, and peak effort. Breath-by-breath gas exchange parameters were collected by indirect calorimetry. Group 1 participants also completed an invasive ramp test during supine rest to determine the impact of varying levels of CF-LVAD support on RV function.

RESULTS

In Group 1, pump speed modulations minimally influenced RV function. During upright exercise, there were modest increases in RV contractility during sub-maximal exercise, but there were no appreciable increases at peak effort. Ventricular‒arterial coupling was preserved throughout the exercise. In Group 2, there were large increases in pulmonary arterial, left-sided filling, and right-sided filling pressures during sub-maximal and peak exercises. Among all participants, the cardiac output‒oxygen uptake relationship was preserved at 5.8:1. Ventilatory efficiency was severely abnormal at 42.3 ± 11.6.

CONCLUSIONS

Patients with CF-LVAD suffer from limited RV contractile reserve; marked elevations in pulmonary, left-sided filling, and right-sided filling pressures during exercise; and severe ventilatory inefficiency. These findings explain mechanisms for persistent reductions in functional capacity in this patient population.

Serum insulin is associated with right ventricle function parameters and lung volumes in subjects free of cardiovascular disease

BACKGROUND

Diabetes mellitus is an established risk factor for cardiovascular diseases. Even impaired levels of glucose and insulin might harm organ function prior to diabetes onset. Whether serum glucose or insulin plays a direct role in cardiac dysfunction or lung volume reduction remains unclear. The aim was to investigate the relationship between glucose and insulin with the right ventricle and lung volumes within KORA-MRI FF4 study.

METHODS

From the KORA-MRI FF4 cohort study 337 subjects (mean age 55.7 ± 9.1 years; 43% women) underwent a whole-body 3T MRI scan. Cardiac parameters derived from a cine-steady-state free precession sequence using cvi42. MRI-based lung volumes derived semi-automatically using an in-house algorithm. Fasting serum glucose, fasting insulin levels, and HOMA index were calculated in all study subjects. Linear regression analyses were performed to assess the relationships between glucose and insulin levels with right ventricle volumes and lung volumes adjusted for age, sex, BMI, and cardiovascular risk factors.

RESULTS

In univariate and multivariate-adjusted models, high serum insulin was inversely associated with end-diastolic volume (β = -12.43, P < 0.001), end-systolic volume (β = -7.12, P < 0.001), stroke volume (β = -5.32, P < 0.001), but not with ejection fraction. The association remained significant after additional adjustment for lung volumes. Similarly, serum insulin was inversely associated with lung volume (β = -0.15, P = 0.04). Sensitivity analysis confirmed results after excluding subjects with known diabetes.

CONCLUSIONS

Serum insulin was inversely associated with right ventricle function and lung volumes in subjects from the general population free of cardiovascular disease, suggesting that increased insulin levels may contribute to subclinical cardiopulmonary circulation impairment.

CTPA pulmonary artery distensibility in assessment of severity of acute pulmonary embolism and right ventricular function

To investigate the characteristics of pulmonary artery distensibility (PAD) in patients with acute pulmonary embolism (APE) and to assess the correlation of PAD with APE severity and right ventricular function. A total of 33 patients who underwent retrospective electrocardiogram (ECG)-gated computed tomography pulmonary angiography (CTPA) with a definite diagnosis of APE were included in the study. According to APE severity, the patients were divided into severe (SPE) and non-severe (NSPE) groups. Data from a control group without APE matching the basic demographics of the APE patients were collected. Pulmonary artery distensibility (PAD) and right ventricular function parameters were compared among the 3 groups, their relationships were investigated, and receiver operating characteristic (ROC) curves were used to determine the sensitivity and specificity of the above parameters for the diagnosis of APE severity. The PAD values of the control, NSPE, and SPE groups were (7.877 ± 2.637) × 10-3 mm/Hg, (6.050 ± 2.011) × 10-3 mm/Hg, (4.321 ± 1.717) × 10-3 mm/Hg, respectively (P < .01). There were statistically significant differences in right ventricular function parameters among the 3 groups (P < .05). The correlation analysis between PAD and right ventricular function parameters showed a weak negative correlation (r = -0.281--0.392). The area under the ROC curve of PAD was 0.743, the critical value was 4.200, and the sensitivity and specificity were 62.5% and 94.1%, respectively. The PAD obtained by retrospective ECG-gated CTPA could accurately evaluate APE severity and right ventricular function. As the severity of APE increases, PAD decreases, which is helpful to identify patients at high risk of APE.

Analysis of the recovery phase after maximal exercise in children with repaired tetralogy of Fallot and the relationship with ventricular function

Background

Few studies demonstrate delayed recovery after exercise in children and adults with heart disease. We assess the recovery patterns of gas exchange parameters and heart rate (HR) in children with repaired Tetralogy of Fallot (rToF) compared to healthy peers and investigate the correlation with ventricular function and QRS duration.

Methods

45 children after rToF and 45 controls performed a maximal incremental cardiopulmonary exercise test. In the subsequent recovery period, patterns of VO₂, VCO₂ and HR were analysed. Half-life time (T_1/2) of the exponential decay and drop per minute (Rec_min) were compared between groups. In the rToF group, correlations were examined between the recovery parameters and QRS-duration and ventricular function, described by fractional shortening (FS) and tricuspid annular plane systolic excursion (TAPSE) measured at baseline prior to exercise.

Results

Recovery of VO₂ and VCO₂ was delayed in rToF patients, half-life time values were higher compared to controls (T_1/2VO₂ 52.51 ±11.29 s vs. 44.31 ± 10.47 s; p = 0.001 and T_1/2VCO₂ 68.28 ± 13.84 s vs. 59.41 ± 12.06 s; p = 0.002) and percentage drop from maximal value was slower at each minute of recovery (p<0.05). Correlations were found with FS (T_1/2VO₂: r = -0.517; p<0.001; Rec_1minVO₂: r = -0.636, p<0.001; Rec_1minVCO₂: r = -0.373, p = 0.012) and TAPSE (T_1/2VO₂: r = -0.505; p<0.001; Rec_1minVO₂: r = -0.566, p<0.001; T_1/2VCO₂: r = -0.466; p = 0.001; Rec_1minVCO₂: r = -0.507, p<0.001), not with QRS-duration. No difference was found in HR recovery between patients and controls.

Conclusions

Children after rToF show a delayed gas exchange recovery after exercise. This delay correlates to ventricular function, demonstrating its importance in recovery after physical activity.

Retrospective single center cohort study: effect of intensive home hemodialysis on right ventricular systolic pressure and clinical outcomes

BACKGROUND

Increased right ventricular systolic pressure (RVSP), a surrogate marker for pulmonary hypertension, is common in patients with end-stage kidney disease. Limited data suggest improvement of RVSP with intensive dialysis, but it is unknown whether these improvements translate to better clinical outcomes.

METHODS

We conducted a retrospective single center cohort study at the Toronto General Hospital. All patients who performed intensive home hemodialysis (IHHD) for at least a year between 1999 and 2017, and who had a baseline as well as a follow-up echocardiogram more than a year after IHHD, were included. Patients were categorized into two groups based on the RVSP at follow-up: elevated (≥ 35 mmHg) and normal RVSP. Multivariate and cox regression analyses were done to identify risk factors for elevated RVSP at follow-up and reaching the composite endpoint (death, cardiovascular hospitalization, treatment failure), respectively.

RESULTS

One hundred eight patients were included in the study. At baseline, 63% (68/108) of patients had normal RVSP and 37% (40/108) having elevated RVSP. After a follow-up of 4 years, 70% (76/108) patient had normal RVSP while 30% (32/108) had elevated RVSP. 8 (10%) out of the 76 patients with normal RVSP and 15 (47%) out of the 32 patients with elevated RVSP reached the composite endpoint of death, cardiovascular hospitalization or technique failure. In a multivariate analysis, age, diabetes and smoking were not associated with elevated RVSP at follow-up. Elevated RVSP at baseline was not associated with a higher likelihood in reaching the composite endpoint or mortality.

CONCLUSION

Mean RVSP did not increase in patients on IHHD over time, and maintenance of normal RVSP was associated with better clinical outcomes.

Impact of right ventricular systolic pressure in elderly patients admitted to intensive care unit after femur fracture surgery: A retrospective observational study

The number of femoral fractures is expected to continue to increase as the size of the older population rapidly grows. However, old age is accompanied by various comorbidities and is an important postoperative risk factor in itself, meaning that patients who undergo surgery for a femur fracture may require admission to an ICU. We investigated pulmonary complications in patients over the age of 65 admitted to the ICU after femur fracture surgery.In this single-center retrospective observational study, 289 patients over 65 years who admitted to the ICU after femur fracture surgery between June 2008 and December 2016 were investigated.Pulmonary complications occurred in 97 of these patients (33.6%) after surgery. Mean hospitalization days (34.1 ± 25.7 vs 23.1 ± 15.7, P < .001) and mean ICU length of stay (8.4 ± 16.1 vs 2.5 ± 1.1, P = .001) were significantly longer for patients with pulmonary complications than for patients without pulmonary complications after femur fracture surgery. Patients with pulmonary complications were significantly more likely to have pulmonary disease (19.6% vs 8.9%, P = .009) and exhibit sequelae on preoperative chest X-rays (9.3% vs 3.6%, P = .048) than were patients without pulmonary complications. In addition, significant differences were observed in the right ventricular systolic pressure (RVSP) measured during preoperative echocardiography (37.4 ± 10.9 mm Hg vs 40.7 ± 9.3 mm Hg for patients without and with pulmonary complications, P = .010) and in the proportion of each group that had an RVSP of >35 mm Hg, which is a marker for pulmonary hypertension (55.2% vs 76.3% for patients without and with pulmonary complications, P < .001). In multivariate analysis, an RVSP of >35 mm Hg during preoperative echocardiography was associated with pulmonary complications after femur fracture surgery (OR, 2.6; 95% CI, 1.45-4.53).In conclusion, Pulmonary complications in older patients admitted to the ICU after femur fracture surgery was associated with longer hospitalization and ICU stays. Preoperative RVSP measurement could identify those older patients with a high risk of pulmonary complications following transferal to the ICU after femur fracture surgery.

Clinical impact of echocardiography-defined pulmonary hypertension on the clinical outcome in patients with multiple myeloma

Pulmonary hypertension (PH) is a complication of multiple myeloma (MM); however, the clinical outcomes and prognosis are relatively not well known. We aimed to investigate the risk factors of transthoracic echocardiography-defined PH and its impact on the clinical outcome in patients with MM.A retrospective study was performed using data from the Chonnam National University Hwasun Hospital database for patients who underwent transthoracic echocardiography (TTE) within 1 month of the MM diagnosis between January 2007 and December 2017. PH was defined as an estimated right ventricular systolic pressure (RVSP) > 40 mmHg. A total of 390 patients were included. TTE-defined PH was observed in 107 patients (27%). During the follow-up period (median, 688 days), all-cause death was noted for 134 patients (34.4%). In the Kaplan-Meier survival analysis, the cumulative overall survival and cardiovascular death-free survival rates were significantly lower in the PH group than in the non-PH group (P < .001). In the propensity score-matched population, RVSP > 40 mmHg on TTE and history of congestive heart failure (CHF) were identified as the significant independent predictors of all-cause and cardiovascular death.This study reports that the prevalence of TTE-defined PH is higher in patients with MM than in the general population. Moreover, TTE-defined PH and a history of CHF are the independent prognostic factors for all-cause and cardiovascular death in patients with MM. These results highlight the risk of associated cardiovascular disease in patients with MM and emphasize the importance of management strategies that prevent the deterioration of cardiac function.

A miniaturized endocardial electromagnetic energy harvester for leadless cardiac pacemakers

Life expectancy of contemporary cardiac pacemakers is limited due to the use of an internal primary battery. Repeated device replacement interventions are necessary, which leads to an elevated risk for patients and an increase of health care costs. The aim of our study is to investigate the feasibility of powering an endocardial pacemaker by converting a minimal amount of the heart's kinetic energy into electric energy. The intrinsic cardiac muscle activity makes it an ideal candidate as continuous source of energy for endocardial pacemakers. For this reason, we developed a prototype able to generate enough power to supply a pacing circuit at different heart rates. The prototype consists of a mass imbalance that drives an electromagnetic generator while oscillating. We developed a mathematical model to estimate the amount of energy harvested from the right ventricle. Finally, the implemented prototype was successfully tested during in-vitro and in-vivo experiments.

Right ventricular strain in repaired Tetralogy of Fallot with regards to pulmonary valve replacement

PURPOSE

To assess right ventricular (RV) myocardial strain both globally and segmentally through feature-tracking cardiac magnetic resonance (CMR) in patients with Tetralogy of Fallot (ToF), with regards to pulmonary valve replacement (PVR).

METHODS

After Ethics Committee approval, we retrospectively included 46 consecutive ToF patients who had two CMR examinations performed at our institution between March 2014 and June 2019. We divided patients into those who had not undergone PVR between the two CMR examinations (Group-0), and those who had (Group-1). Ventricular volumes were quantified on cine sequences, and strain was calculated through feature-tracking, using the previously traced segmentations. RV longitudinal and radial strain were assessed both globally and separately for the septum and free wall. Variations were normalized for intercurrent years, differences were appraised with t-tests or Mann-Whitney U.

RESULTS

30 patients belonged to Group-0 and 16 to Group-1. Median age was 22 years (interquartile range [IQR] 17-29 years) in Group-0, and 21 years (IQR 16-29 years) in Group-1. No significant differences were reported in RV strain between groups (p ≥ 0.254) except for RV septal radial strain, significantly higher (p = 0.010) in Group-0 (24.2 %, IQR 10.1-52.4 %) than in Group-1 (6.0 %, IQR -3.3-23.3 %) at the second CMR. Both global and segmental RV strains decreased over time in both groups, and yearly variations did not differ significantly (p ≥ 0.081) between groups.

CONCLUSIONS

While PVR performed at the appropriate timing eases the burden on the RV allowing for a reduction in volumes, RV strain seems to continuously deteriorate as in patients who do not undergo PVR.