Commonly Used Respiratory and Pharmacologic Interventions in the Echocardiography Laboratory

Update of clinical echocardiographic assessment of heart failure with preserved ejection fraction

PURPOSE OF REVIEW

Heart failure with preserved ejection fraction (HFpEF) has an increasing global prevalence. Diastolic dysfunction is the predominant cause of symptoms, most commonly, exertional dyspnea. Although prevalent, the syndrome is challenging to identify due to the comorbid conditions that can present similarly. This paper will review established, guideline recommended, echocardiographic variables, and pathophysiology.

RECENT FINDINGS

Echocardiography is the primary diagnostic modality. The latest advances in strain analysis, algorithmic use of multiple parameters, and deeper understanding of exercise hemodynamics have improved our classification of those with HFpEF.

SUMMARY

There remains a paucity of therapies with mortality benefit in this subgroup. Thus, improving diagnostic efficacy is important as it can clarify epidemiologic, phenotypic, and pathologic features of HFpEF.

A Simple Method for Noninvasive Quantification of Pressure Gradient Across the Pulmonary Valve

Pressure gradient across the pulmonary valve (PVPG) is an important hemodynamic variable used in the management of patients with cardiovascular and pulmonary disease. However, a reliable noninvasive method is unavailable. We hypothesized that a progressive Muller maneuver would elicit the pulmonary valve premature opening (PVPO) in diastole and that this event would be detectable by Doppler echocardiography. The intrathoracic pressure (ITP) decrease during this maneuver equals PVPG, which may be assessed with a custom airway pressure measurement device. A total of 102 subjects were enrolled in the study. At the earliest appearance of PVPO, the ITP decrease was recorded as the PVPG. PVPG was also simultaneously measured and compared by other two methods: right heart catheterization in 43 subjects, and routine Doppler echocardiography (pulmonary regurgitation jet) in the other 59 subjects. The results measured by different approaches were compared using the Bland-Altman analysis. PVPG assessed via PVPO showed strong agreement with PVPG measured by catheterization or routine Doppler echocardiography methods, with Lin concordance correlation coefficients of 0.91 and 0.70, respectively. In conclusion, PVPO provides a new noninvasive method of quantification of PVPG.

Respiratory maneuvers in echocardiography: a review of clinical applications

During echocardiographic examination, respiration induces cyclic physiological changes of intracardiac haemodynamics, causing normal variations of the right and left ventricle Doppler inflows and outflows and physiological variation of extracardiac flows. The respiration related hemodynamic variation in intra and extracardiac flows may be utilized in the echocardiography laboratory to aid diagnosis in different pathological states. Nevertheless, physiologic respiratory phases can cause excessive translational motion of cardiac structures, lowering 2D image quality and interfering with optimal Doppler interrogation of flows or tissue motion.

This review focuses on the impact of normal respiratory cycle and provocative respiratory maneuvers in echocardiographic examination, both in physiological and pathological states, emphasizing their applications in specific clinical situations.