Long-term exercise intolerance and functional limitations are common after an episode of acute pulmonary embolism (PE), despite 3 to 6 months of anticoagulation. These persistent symptoms are reported in more than half of the patients with acute PE and are referred as "post-PE syndrome." Although these functional limitations can occur from persistent pulmonary vascular occlusion or pulmonary vascular remodeling, significant deconditioning can be a major contributing factor. Herein, the authors review the role of exercise testing to elucidate the mechanisms of exercise limitations to guide next steps in management and exercise training for musculoskeletal deconditioning.

Invasive cardiopulmonary exercise testing (iCPET) is increasingly recognized as a critical diagnostic tool for assessing exercise intolerance and dyspnea. The manuscript highlights the iCPET program's diagnostic precision in identifying various cardiopulmonary disorders, offering insights into tailored treatment strategies. This guide aims to assist institutions in establishing their iCPET programs, addressing both the technical and administrative facets essential for success. The narrative is rooted in personal experiences, reflecting on the demanding, yet rewarding, journey of enhancing patient care through advanced diagnostic capabilities.

Exercise testing is frequently incorporated into management of patients with cardiovascular and/or pulmonary disease. A lifelong commitment to exercise promotes cardiac remodeling, leading to changes in structure and function of the atria and ventricles, commonly referred to as the "athletic heart." Stress testing is also incorporated into the management of athletes for a variety of reasons, such as identifying the cause of exertional symptoms, determining level of fitness and training zones, or assessing for acquired cardiomyopathies. Exercise testing should be tailored to the athlete, since performance may vary from other populations as a result of a commitment to exercise training.

Of the 5 randomized controlled trials (RCTs) included, chronic thromboembolic pulmonary hypertension (CTEPH) patients constituted 20% of the overall pulmonary hypertension (PH) patient population. We did not find any RCTs that evaluated the role of exercise training in patients with CTEPH. The results of this study indicate that exercise training may be effective at improving exercise capacity, as measured by 6-min walk distance, in patients with PH. Another notable finding from this analysis is the lack of adverse events associated with exercise training, suggesting that contrary to widespread perception, exercise training is safe in CTEPH and PAH patients.

Cardiopulmonary exercise testing (CPET) permits the assessment of gas exchange, electrocardiogram, and hemodynamic patterns throughout exercise, providing a window into multi-organ physiologic reserve during exercise. CPET provides risk stratification and informs management of advanced heart failure (HF). Increasingly, CPET is combined with echocardiography, or invasive right heart catheterization, which enables high-resolution assessment of cardiac and extracardiac limitations to exercise. CPET also represents a cornerstone in the evaluation process for advanced HF interventions. This review underscores the importance and utility of CPET in managing patients with advanced HF.

Exercise intolerance is common in patients with heart failure with preserved ejection fraction. This review will discuss the utility of exercise hemodynamics under both diagnostic and prognostic circumstances and highlight challenges associated with making and interpreting measures taken during exercise.

Pulmonary arterial hypertension (PAH) is a progressive pulmonary vascular disease that has a high impact on patients' quality of life, morbidity and mortality. PAH is characterized by extensive pulmonary vascular remodeling that results in an increase in pulmonary vascular resistance and right ventricular afterload, and can lead to right heart failure. Patients with PAH exhibit inefficient ventilation, high dead space ventilation, dynamic hyperinflation, and ventricular-arterial uncoupling, which can contribute to high dyspnea and low exercise tolerance. Cardiopulmonary exercise testing can help to diagnose PAH, define prognosis and treatment response in PAH, as well as discriminate between different pulmonary vascular diseases.

The pulmonary circulation and the right ventricle play a pivotal role in the global hemodynamics of human beings, so much so that their close interaction is encapsulated in the concept of a "morpho-functional unit". In this review we aim to pinpoint the strengths and weaknesses of various noninvasive established techniques. The goal is to detect early morphologic and/or functional changes in the pulmonary circulation and right ventricular unit, which is crucial for tailoring treatments and prognostic assessments. The scope of this review includes resting and stress echocardiography, cardiopulmonary exercise testing, computed tomography, and cardiac magnetic resonance in characterizing the pulmonary circulation-right ventricular unit both morphologically and functionally.

The invasive cardiopulmonary exercise test (iCPET) provides a comprehensive, simultaneous evaluation of an individual's cardiovascular, respiratory, and metabolic response to exercise. The test is uniquely suited for the evaluation of exercise intolerance, as well as the deep phenotyping of disease states including pulmonary arterial hypertension and post-coronavirus disease symptomatology. Despite an expanding list of clinical and research applications, both the complexity of the test and a lack of familiarity with how the test is performed have been barriers to the widespread use of iCPET. The aim of this article is to provide practical insights into how an iCPET is performed.

Exercise pulmonary hypertension has been invasively defined as mean pulmonary artery pressure/cardiac output slope greater than 3 mm Hg/L/min. Recent advances suggest the sustainable role of exercise Doppler echocardiography for the study of the right heart and pulmonary circulation unit (RH-PCU). Herein, the authors review the invasive versus non-invasive monitoring of the RH-PCU response to exercise in healthy subjects.

Cardiopulmonary exercise testing is an active research area in patients with unexplained dyspnea, heart failure, and pulmonary hypertension. Focus has centered on the use of novel hemodynamic parameters to further characterize these disease states, influence therapeutics, and determine prognosis. Translational research focuses on the underlying cardiopulmonary physiology to more precisely quantify the effect of pulmonary vascular disease on the right ventricle and pulmonary function/hemodynamics. In addition, phenotyping unexplained dyspnea is of critical importance, given the significant heterogeneity of this patient population with implications for therapies and clinical trial design.

Frailty affects half of all patients with heart failure with reduced ejection fraction (HFrEF) and carries a ∼2-fold increased risk of mortality. The relationship between frailty and HFrEF is bidirectional, with one condition exacerbating the other. Paradoxical to their higher clinical risk, frail patients with HFrEF are more often under-treated due to concerns over medication-related adverse clinical events. However, current evidence suggests consistent safety of HF medical therapies among older frail patients with HFrEF. A multidisciplinary effort is necessary for the appropriate management of these high-risk patients which focuses on the optimization of known beneficial therapies with a goal-directed effort toward improving quality of life.

The conventional sequence of guideline-directed medical therapy (GDMT) initiation in heart failure with reduced ejection fraction (HFrEF) assumes that the effectiveness and tolerability of GDMT agents mirror their order of discovery, which is not true. In this review, the authors discuss flexible GDMT sequencing that should be permitted in special populations, such as patients with bradycardia, chronic kidney disease, or atrial fibrillation. Moreover, the initiation of certain GDMT medications may enable tolerance of other GDMT medications. Most importantly, the achievement of partial doses of all four pillars of GDMT is better than achievement of target dosing of only a couple.

Life-threatening dysrhythmias remain a significant cause of mortality in patients with nonischemic cardiomyopathy (NICM). Implantable cardioverter-defibrillators (ICD) effectively reduce mortality in patients who have survived a life-threatening arrhythmic event. The evidence for survival benefit of primary prevention ICD for patients with high-risk NICM on guideline-directed medical therapy is not as robust, with efficacy questioned by recent studies. In this review, we summarize the data on the risk of life-threatening arrhythmias in NICM, the recommendations, and the evidence supporting the efficacy of primary prevention ICD, and highlight tools that may improve the identification of patients who could benefit from primary prevention ICD implantation.

Obesity has been long recognized as a risk factor for the development of heart failure, but recent evidence suggests obesity is more typically associated with heart failure with preserved ejection fraction as opposed to heart failure with reduced ejection fraction (HFrEF). Nevertheless, numerous studies have found that obesity modulates the presentation and progression of HFrEF and may contribute to the development of HFrEF in some patients. Although obesity has definite negative effects in HFrEF patients, the effects of intentional weight loss in HFrEF patients with obesity have been poorly studied.

Successful remote patient monitoring depends on bidirectional interaction between patients and multidisciplinary clinical teams. Invasive pulmonary artery pressure monitoring has been shown to reduce heart failure (HF) hospitalizations, facilitate guideline-directed medical therapy optimization, and improve quality of life. Cardiac implantable electronic device-based multiparameter monitoring has shown encouraging results in predicting future HF-related events. Potential expanded indications for remote monitoring include guideline-directed medical therapy optimization, application to specific populations, and subclinical detection of HF. Voice analysis, inferior vena cava diameter monitoring, and artificial intelligence-based remote electrocardiogram show potential to gain some merit in remote patient monitoring in HF.

Transcatheter mitral valve repair should be considered for patients with severe secondary mitral regurgitation with symptomatic heart failure with reduced ejection fraction for symptom improvement and survival benefit. Patients with a higher severity of secondary mitral regurgitation relative to the degree of left ventricular dilation are more likely to benefit from transcatheter mitral valve repair. A multidisciplinary Heart Team should participate in patient selection for transcatheter mitral valve therapy.

Cardiogenic shock is a multisystem pathology that carries a high mortality rate, and initial pharmacotherapies include the use of vasopressors and inotropes. These agents can increase myocardial oxygen consumption and decrease tissue perfusion that can oftentimes result in a state of refractory cardiogenic shock for which temporary mechanical circulatory support can be considered. Numerous support devices are available, each with its own hemodynamic blueprint. Defining a patient's hemodynamic profile and understanding the phenotype of cardiogenic shock is important in device selection. Careful patient selection incorporating a multidisciplinary team approach should be utilized.

Heart failure (HF) is a progressive disease. It is estimated that more than 250,000 patients suffer from advanced HF with reduced ejection fraction refractory to medical therapy. With limited donor pool for heart transplant, continue flow left ventricle assist device (LVAD) is a lifesaving treatment option for patients with advanced HF. This review will provide an update on indications, contraindications, and associated adverse events for LVAD support with a summary of the current outcomes data.