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Advanced Therapeutic Options in Acute Heart Failure
Published in Andreas P. Kalogeropoulos, Hal A. Skopicki, Javed Butler, Heart Failure, 2023
Tiffany Dong, Aditi Nayak, Alanna Morris
Many patients who qualify for inotropic or mechanical support may require a pulmonary artery catheter (PAC) to assess hemodynamics. The catheter measures filling pressures from which cardiac output and pulmonary and systemic vascular resistance can be derived. While PAC may be useful in certain contexts, data have not shown benefit consistently. In the ESCAPE trial, 433 patients with left ventricular ejection fraction (LVEF) <30% and symptoms of congestion were randomized to PAC or clinical assessment alone with the primary endpoint of 60-day survival after discharge. The trial was discontinued due to PAC complications and futility. However, only 180 patients in the trial required inotropes and thus PACs may still be indicated.17 The guidelines recommend PAC use in patients with respiratory distress or decreased perfusion when cardiac filling pressures cannot be clinically ascertained (class I, level of evidence C). There is a class IIA indication with level C evidence for ADHF refractory to standard therapy if there is uncertainty regarding hemodynamics, persistently low systolic blood pressure, worsening renal function, use of IV vasoactive medications, or when considering MCS or transplant.3
Multiple pregnancy and infertility
Published in Janetta Bensouilah, Pregnancy Loss, 2021
All maternal organ systems are required to adapt to the demands of pregnancy, and these normal physiological adaptations in the mother are heightened in multiple pregnancy: Renal blood flow increases.Systemic vascular resistance decreases.Cardiac output increases.Red cell mass increases by around 300 ml more than in singletons, but haemoglobin values fall.
Complications of hemodialysis access
Published in Sachinder Singh Hans, Mark F. Conrad, Vascular and Endovascular Complications, 2021
Mia Miller, Prakash Jayanthi, William Oppat
Development of high-output heart failure is an underappreciated complication in patients. As a fistula shunts blood from the arterial circulation to venous circulation bypassing capillary resistance, there is increased preload, as well as decreased systemic arterial flow. Fistula flow in a well-functioning fistula is approximately 700–1500 mL/min.73 Over time, this leads to left ventricular hypertrophy, reduced ejection fraction, and heart failure. Symptoms include tachycardia, elevated pulse pressure, dyspnea on exertion, fluid retention, and jugular venous distension.74 On physical examination, the fistula appears large with rapid flow and aneurysmal growth, often times referred to as a “mega-fistula”.75 Workup begins with an echocardiogram to document left ventricular function, and investigation to rule out other etiologies of high-output heart failure. Elevated levels of biochemical assays such as ANP and BNP confirm volume expansion. To determine high-output heart failure as the definitive cause, a right heart catheterization is required. Characteristic findings include pulmonary hypertension with normal pulmonary vascular resistance and high cardiac output with low-normal systemic vascular resistance.74
Acute kidney injury in COVID 19 – an update on pathophysiology and management modalities
Published in Archives of Physiology and Biochemistry, 2023
Manoj Khokhar, Purvi Purohit, Dipayan Roy, Sojit Tomo, Ashita Gadwal, Anupama Modi, Mithu Banerjee, Praveen Sharma
The careful monitoring of intravascular volume status is a crucial tenet of conservative fluid management in cardiovascular and renal injury (Matthay et al.2020, p. 19). In the backdrop of sepsis-induced coagulopathy, mechanical ventilation with high PEEP can increase the risk of development of pulmonary hypertension, right heart failure, and hypoperfusion (Tang et al.2020). The currently available standard monitors have a low capability of identifying end-organ damage, thus contributing to increased risk of morbidity and mortality (Table 3). Pulmonary artery catheter (PAC) has shown promise in this regard because it can measure right atrial and right ventricular pressures as well as continuous mixed venous oxygen saturation (SvO2). Additionally, systemic vascular resistance (SVR), and cardiac output can also be measured (D'Alto et al.2018). This helps in minimising the expenditure of hospital resources and maximises monitoring sensitivity. The vigilant monitoring of hemodynamic status and fluid imbalance in COVID-19 associated AKI would help to tide over the period of renal impairment with better outcomes. Further, Ponce et al. (2020) described the workflow for the delivery and monitoring of peritoneal dialysis for patients without the risk of respiratory impairment.
New and developing pharmacotherapies for hypertension
Published in Expert Review of Cardiovascular Therapy, 2022
Christian Höcht, Miguel A Allo, Ariel Héctor Polizio, Marcela A Morettón, Andrea Carranza, Diego A Chiappetta, Marcelo Roberto Choi
Restoration of NO-soluble GC (sGC)–cGMP signaling has emerged as a potentially new pharmacological target for the chronic management of arterial hypertension [72]. One factor that contributes to the elevated systemic vascular resistance in hypertensive patients is the low bioavailability of NO [66]. Reduced levels of endogenous NO led to lower cGMP production and impairment of cGMP downstream signaling. cGMP does not only exert potent vasodilatory effects but also contributes to tissue homeostasis through antifibrotic and anti-inflammatory actions [73]. Traditionally, NO donors, such as sodium nitroprusside, have been used for the early control of BP in patients with hypertensive emergencies [72]. However, the utility of NO donors for the chronic management of arterial hypertension is limited by their poor pharmacokinetic properties and the development of tolerance to the BP lowering effect [72].
Antihypertensive treatment and risk factors for syncope in asymptomatic aortic stenosis patients with hypertension
Published in Clinical and Experimental Hypertension, 2022
Meihua Wu, Ping Gu, Qianqiang Cao, Aibin Gong, Wenliang Tan, Dezhi Hong
To assess diastolic function, peak early diastolic velocity (E), peak late diastolic velocity (A), and E/A ratio were derived from Doppler recordings of transmitral flow. Zva was calculated as the sum of systolic blood pressure (SBP) and mean transaortic pressure gradient divided by the SVi (9). We also calculated the ratio of SVi to brachial pulse pressure (SVi/PP) as an index of systemic arterial compliance (10). Systemic vascular resistance was estimated using the following formula: (80× mean blood pressure)/cardiac output. The LV end-diastolic volume was determined using the Teichholz method. The LV stroke volume was calculated as the product of the LV outflow tract cross-sectional area and the outflow tract time-velocity integral. LV mass was calculated using the method of Devereux et al (11). Relative wall thickness was determined as the ratio of end-diastolic wall thickness to the end-diastolic radius, where the radius was half of the minor axis diameter (12).