"From right to left": The role of right heart catheterization in the diagnosis and management of left heart diseases

Electrocardiogram Parameters Associated With the Diagnosis of Pulmonary Hypertension in High-Altitude Tibetan Populations: A Retrospective Single-Centre Study

BACKGROUND

Electrocardiogram (ECG) is a commonly used diagnostic method for pulmonary hypertension (PH) in Tibetan areas, but its sensitivity and specificity are not good enough. This study aimed to investigate the ECG parameters associated with the diagnosis of PH in Tibetan areas.

METHODS

Ninety-four PH patients of Tibetan ethnicity who were treated at the hospital between March 2019 and October 2020, and 52 Tibetan individuals as controls, were included. The ECG parameters were compared between groups. Multivariate logistic analysis was performed to identify the ECG parameters that can be used for the diagnosis of PH. The univariate significances of ECG parameters were included in the multivariate analyses, whereas those exhibiting opposite trends between different PH subtypes were excluded.

RESULTS

Two ECG parameters were significant in multivariate analysis. The final model included S wave amplitude in lead V3 (OR 5.81; 95% CI 2.79-12.11; p<0.001) and a negative T wave in leads V1-V3 (OR 0.05; 95% CI 0.01-0.41; p=0.005). The ROC curve analysis on the final model yielded an AUC of 0.830 (95% CI 0.766-0.894; p<0.001), indicating good diagnostic performance. A nomogram for diagnosis of PH was also established using S wave amplitude in lead V3 and a negative T wave in leads V1-V3.

CONCLUSION

The ECG parameters S wave amplitude in lead V3 and a negative T wave in leads V1-V3 were independent factors associated with the diagnosis of PH in high-altitude Tibetan populations.

Complications of Right Heart Catheterization in Patients ≥70 Years of Age With Suspected Pulmonary Hypertension: Experience From a Tertiary Care Center

Right heart catheterization (RHC) represents the gold standard diagnostic approach for pulmonary hypertension (PH). Historically, the complication rates of RHC are known to be low. The study aimed to evaluate the indications for performing RHC and the occurrence of adverse events related to the procedure in patients > over 70 years of age in a Mexican Tertiary Care Center. We conducted a retrospective single-center registry from July 2017 to July 2022. A total of 517 patients with suspected PH underwent RHC. The cohort included patients <70 (n = 427) and ≥70 years of age (n = 90). Adverse events were classified as major (eg, death, pneumothorax, and carotid artery puncture) and minor (eg, atrial arrhythmia, superior vena cava dissection, incidental arterial puncture, and local hematoma). Appropriate hemodynamic parameters were recorded. No report of major adverse events in the entire cohort. In the <70 years age group, 9 minor events, and 3 minor events were in the ≥70-year-old patients (P < 0.0001). There was a significant difference in the measurement of mean pulmonary artery pressure (mPAP) between the <70 years old vs ≥70 years old (P < 0.001); there was a significant difference in right atrial pressures: 4.71 ± 3.14 mmHg in the <70-year-old vs 4.07 ± 1.94 mmHg for the ≥ 70-year-old group (P = 0.014). Our findings suggest that RHC can be safely performed in patients aged ≥70 years using different vascular access routes without significant major complications.

Bioimpedance based determination of cardiac index does not show enough trueness for point of care use in patients with systolic heart failure

Cardiac output (CO) is a key parameter in diagnostics and therapy of heart failure (HF). The thermodilution method (TD) as gold standard for CO determination is an invasive procedure with corresponding risks. As an alternative, thoracic bioimpedance (TBI) has gained popularity for CO estimation as it is non-invasive. However, systolic heart failure (HF) itself might worsen its validity. The present study validated TBI against TD. In patients with and without systolic HF (LVEF ≤ 50% or > 50% and NT-pro-BNP < 125 pg/ml, respectively) right heart catheterization including TD was performed. TBI (Task Force Monitor©, CNSystems, Graz, Austria) was conducted semi-simultaneously. 14 patients with and 17 patients without systolic HF were prospectively enrolled in this study. In all participants, TBI was obtainable. Bland-Altman analysis indicated a mean bias of 0.3 L/min (limits of agreement ± 2.0 L/min, percentage error or PE 43.3%) for CO and a bias of -7.3 ml (limits of agreement ± 34 ml) for cardiac stroke volume (SV). PE was markedly higher in patients with compared to patients without systolic HF (54% vs. 35% for CO). Underlying systolic HF substantially decreases the validity of TBI for estimation of CO and SV. In patients with systolic HF, TBI clearly lacks diagnostic accuracy and cannot be recommended for point-of-care decision making. Depending on the definition of an acceptable PE, TBI may be considered sufficient when systolic HF is absent.Trial registration number: DRKS00018964 (German Clinical Trial Register, retrospectively registered).

Estimation of Physiologic Pressures: Invasive and Non-Invasive Techniques, AI Models, and Future Perspectives

The measurement of physiologic pressure helps diagnose and prevent associated health complications. From typical conventional methods to more complicated modalities, such as the estimation of intracranial pressures, numerous invasive and noninvasive tools that provide us with insight into daily physiology and aid in understanding pathology are within our grasp. Currently, our standards for estimating vital pressures, including continuous BP measurements, pulmonary capillary wedge pressures, and hepatic portal gradients, involve the use of invasive modalities. As an emerging field in medical technology, artificial intelligence (AI) has been incorporated into analyzing and predicting patterns of physiologic pressures. AI has been used to construct models that have clinical applicability both in hospital settings and at-home settings for ease of use for patients. Studies applying AI to each of these compartmental pressures were searched and shortlisted for thorough assessment and review. There are several AI-based innovations in noninvasive blood pressure estimation based on imaging, auscultation, oscillometry and wearable technology employing biosignals. The purpose of this review is to provide an in-depth assessment of the involved physiologies, prevailing methodologies and emerging technologies incorporating AI in clinical practice for each type of compartmental pressure measurement. We also bring to the forefront AI-based noninvasive estimation techniques for physiologic pressure based on microwave systems that have promising potential for clinical practice.

Mechanism of histone deacetylases in cardiac hypertrophy and its therapeutic inhibitors

Cardiac hypertrophy is a key process in cardiac remodeling development, leading to ventricle enlargement and heart failure. Recently, studies show the complicated relation between cardiac hypertrophy and epigenetic modification. Post-translational modification of histone is an essential part of epigenetic modification, which is relevant to multiple cardiac diseases, especially in cardiac hypertrophy. There is a group of enzymes related in the balance of histone acetylation/deacetylation, which is defined as histone acetyltransferase (HAT) and histone deacetylase (HDAC). In this review, we introduce an important enzyme family HDAC, a key regulator in histone deacetylation. In cardiac hypertrophy HDAC I downregulates the anti-hypertrophy gene expression, including Kruppel-like factor 4 (Klf4) and inositol-5 phosphatase f (Inpp5f), and promote the development of cardiac hypertrophy. On the contrary, HDAC II binds to myocyte-specific enhancer factor 2 (MEF2), inhibit the assemble ability to HAT and protect against cardiac hypertrophy. Under adverse stimuli such as pressure overload and calcineurin stimulation, the HDAC II transfer to cytoplasm, and MEF2 can bind to nuclear factor of activated T cells (NFAT) or GATA binding protein 4 (GATA4), mediating inappropriate gene expression. HDAC III, also known as SIRTs, can interact not only to transcription factors, but also exist interaction mechanisms to other HDACs, such as HDAC IIa. We also present the latest progress of HDAC inhibitors (HDACi), as a potential treatment target in cardiac hypertrophy.

Clinical, echocardiographic and hemodynamic predictors of right heart failure after LVAD placement

Right ventricular failure (RVF) after left ventricular assist device (LVAD) implant is associated with increasing morbidity and mortality. The aim of this study was to identify the best predictors of RVF post LVAD-implant among biochemical, haemodynamic and echocardiographic parameters. From 2009 to 2019, 38 patients who underwent LVAD implantation at our centre were prospectively enrolled. Preoperative clinical, laboratory, echocardiographic and haemodynamic parameters were reported. Overall, eight patients (21%) developed RVF over time, which revealed to be strongly related to overall mortality. Pulmonary artery pulsatility index (PAPi) resulted to be the most significant right heart catheterization index in discriminating RVF vs no RVF patients [(1.32 ± 0.26 vs. 3.95 ± 3.39 respectively) p = 0.0036]. Regarding transthoracic echocardiography, RVF was associated with reduced free wall right ventricular longitudinal strain (fw-RVLS) (- 7.9 ± 1.29 vs. - 16.14 ± 5.83) (p < 0.009), which was superior to other echocardiographic determinants of RVF. Among laboratory values, N-terminal pro-brain natriuretic peptide (NT-proBNP) was strongly increased in RVF patients [(10,496.13 pg/ml ± 5272.96 pg/ml vs. 2865, 5 pg/ml ± 2595.61 pg/ml) p = 0.006]. PAPi, NT-proBNP and fwRVLS were the best pre-operative predictors of RVF, a post-LVAD implant complication which was confirmed to have a great impact on survival. In particular, fwRVLS has been proven to be the strongest independent predictor.

Radiological and hemodynamic parameters in patients with suspected ventricular aneurysm and interventricular septal perforation after acute myocardial infarction: A comparison of non-invasive and invasive diagnostic modalities

Transthoracic echocardiography is a rapid, sensitive and non-invasive technique for diagnosing ventricular septal perforation. Furthermore, left ventricular angiography is generally used for left ventricular aneurysm but right heart catheterization is the gold standard for septal perforation following myocardial infarction. The objectives of the present study were to compare radiological and hemodynamic diagnostic parameters of non-invasive methods with those of right heart catheterization in patients with suspected ventricular aneurysm and interventricular septal perforation after acute myocardial infarction. Data regarding demographics and clinical characteristics, as well as right heart catheterization, echocardiography and angiographic parameters of 199 patients examined within 21 days after myocardial infarction due to suspected ventricular septal defect indicated by persistent colic pain in the pre-cardiac region were collected and analyzed. Coronary angiography identified 149 (75%) patients with single-vessel disease, 42 (21%) patients with two-vessel disease and 8 (4%) patients with triple-vessel disease. Transthoracic color Doppler echocardiography strengthened the diagnostic performance of right heart catheterization regarding segmental motor abnormalities but underestimated the right atrial pressure, systolic pulmonary artery pressure, mean pulmonary artery pressure and pulmonary capillary wedge pressure compared with right heart catheterization (P<0.0001 for all). Overall, there was no procedural complication requiring emergency intervention, no major complications and no conditions resulting in death due to diagnostic modalities. Transthoracic color Doppler echocardiography may strengthen the diagnostic performance of right heart catheterization regarding radiological measurements but underestimated hemodynamic measurements (level of evidence: 3).

Posttransplant Pulmonary Hypertension Is Correlated With Acute Rejection and Death Among Cardiac Transplant Recipients: A Single Center Study

OBJECTIVES

Endomyocardial biopsy sampling is used to check acute rejection after cardiac transplant. However, it may lead to tricuspid valve injury and cardiac perforation; therefore, less invasive tools may be useful. Right heart catheterization provides valuable information about cardiac hemodynamics. Herein, we aimed to determine the correlation of right heart catheterization parameters with acute rejection and death during cardiac transplant follow-up.

MATERIALS AND METHODS

We retrospectively evaluated follow-up right heart catheterization and endomyocardial biopsy results from 47 adult patients who underwent cardiac transplant at Başkent University Faculty of Medicine between 2004 and 2016. Right heart catheterization parameters were compared between deceased and surviving patients and were correlated with acute cellular and humoral rejection. Averaged right heart catheterization parameters were correlated with death. We used Cox regression analysis to determine risk of death and acute cellular rejection and Kaplan-Meier survival analysis to determine any survival differences associated with pulmonary hypertension.

RESULTS

There were 47 patients (38 males, 9 females) with a mean age of 44 ± 10 years at transplant. In our patient group, 18 patients (38.3%) died at a median time of 11.2 months. Ninety endomyocardial biopsy samples (22.1%) showed cellular rejection, and 61 samples (4.5%) showed humoral rejection. The deceased patients had significantly greater mean and systolic pulmonary artery pressures, which were significantly correlated with acute cellular rejection. Death was significantly correlated with averaged values of mean and systolic pulmonary artery pressures. Our Cox regression analysis revealed that pulmonary hypertension was significantly associated with risk of death and acute cellular rejection. A Kaplan-Meier survival analysis revealed that pulmonary hypertension was associated with a significantly lower median survival.

CONCLUSIONS

Pulmonary artery pressures are significantly correlated with acute cellular rejection and death after cardiac transplant. Pulmonary hypertension significantly increases the risk of death and shortens survival after cardiac transplant.

Right heart catheterization procedures in patients with suspicion of pulmonary hypertension - experiences of a tertiary center

INTRODUCTION

Right heart catheterization (RHC) is an invasive procedure providing direct and accurate measurements of hemodynamics of the cardiovascular system. Acute pulmonary vasoreactivity testing (APVT) following basal RHC in some patients is an established tool evaluating the reversibility of hypertension in the pulmonary vasculature.

AIM

We sought to assess the most common indications, vascular approaches and complications during RHC in a single high-volume center.

MATERIAL AND METHODS

A total of 534 RHC procedures in 348 patients (64% male) were performed. The prospective registry was carried out for 28 months. Collected data included indications for RHC, vascular approaches, hemodynamic and clinical data, complications and response of pulmonary vessels in APVT.

RESULTS

In 401 (75%) procedures pulmonary hypertension (mean pulmonary artery pressure (mPAP) ≥ 25 mm Hg) was confirmed. Left heart failure was the most common indication (55.8%), mainly ischemic (26%) or dilated cardiomyopathy (19.9%). Other indications included a suspicion of arterial (21.7%), or chronic thromboembolic pulmonary hypertension (14.6%). The right internal jugular vein approach was used in 89.1% of procedures. Acute pulmonary vasoreactivity testing was performed in 143 patients, and it was positive in 67 (46.9%) cases. Complications occurred in 21 (3.9%) procedures and included pulmonary edema (0.2%), pneumothorax (0.2%) and puncture of the artery followed by the insertion of a vascular sheath (0.4%), atrial arrhythmia (0.2%), superior vena cava dissection (0.2%), incidental artery puncture (1.1%) and local hematoma (2.2%).

CONCLUSIONS

The most frequent indication for RHC was left heart failure, and the most common approach was the right internal jugular vein. RHC is safe procedure with a low rate of major complications.