The feasibility of using continuous on-line recording of intraventricular electrical impedance to measure ventricular stroke volume was assessed in 12 patients at cardiac catheterization with a multielectrode impedance catheter and a 1.3 kHz measuring current of 4 ,A. Stroke volumes determined by electrical impedance were compared with stroke volumes determined by the thermodilution technique in 10 patients and correlated with an r value of .95. Directional changes in impedance recordings throughout the cardiac cycle were also compared with volume curves obtained from six patients by radionuclide ventriculography, and in all instances the agreement between the two volume recordings was excellent. For all patients, on-line measurements of impedance showed a beat-by-beat decrease in stroke volume with the Valsalva maneuver and the administration of amyl nitrite, as well as an immediate increase in stroke volume in the contraction following an extra-systolic beat. Similar directional changes in stroke volume were recorded in both left and right ventricles. Left ventricular pressure-volume relationships were assessed with simultaneous left ventricular pressure recordings and volume signals recorded from the impedance catheter to determine if impedance measurements of volume can be used clinically. Pressure-volume diagrams were subsequently plotted, and for all patients these diagrams showed characteristic isovolumetric contraction and relaxation phases as well as typical ejection and filling periods. Moreover, beat-by-beat sequential pressure-volume diagrams constructed for patients during the administration of amyl nitrite revealed a linear end-systolic pressure-volume relationship. We conclude that measurement of intracavitary electrical impedance can be used to monitor instantaneous changes in stroke volume in patients and may be helpful in the construction of pressure-volume diagrams and the assessment of left ventricular end-systolic pressure-volume relationships. Circulation 69, No. 4, 703-710, 1984

Transcatheter aortic valve replacement (TAVR) is an established treatment for severe, symptomatic, aortic stenosis (AS) in patients of all risk categories and now comprises 12.5% of all aortic valve replacements. TAVR is a less invasive alternative to traditional surgical aortic valve replacement (SAVR), with equivalent or superior outcomes. The use of TAVR has increased rapidly. The success and increase in use of TAVR are a result of advances in technology, greater operator experience, and improved outcomes. Indications have recently expanded to include patients considered to be at low risk for SAVR. While TAVR outcomes have improved, remaining challenges include the management of coexistent coronary artery disease, prevention of periprocedural stroke, and issue of durability. These issues are even more relevant for low-risk, younger patients.

Apixaban is a rare cause of leukocytoclastic vasculitis (LCV). To our knowledge, there is only one other reported case due to apixaban in the literature. We present a case of apixaban-induced leukocytoclastic vasculitis in a 95-year-old male. He had been started on apixaban 12 days prior to presentation and developed worsening palpable purpura of his lower extremities. Possible etiologies of this new rash were excluded, with biopsy showing extensive purpura with superficial perivascular neutrophilic infiltrate and leukocytoclasis. Apixaban was discontinued, and the patient was started on a slow prednisone taper with subsequent resolution of his rash.

Coexisting carotid artery stenosis and coronary artery disease is common and there is currently no consensus in treatment guidelines on the timing, sequence and methods of revascularization. We report a case of a patient with symptomatic triple vessel coronary artery disease as well as asymptomatic severe right internal carotid artery stenosis. Our patient underwent myocardial revascularization first, because she presented with unstable angina and was asymptomatic neurologically. This article summarizes current literature about the approach to carotid and coronary artery revascularization and addresses the decision-making process regarding the timing and sequence of revascularization.

No abstract

No abstract

Background Effusive–constrictive pericarditis (ECP) is a rare syndrome involving pericardial effusion and concomitant constrictive pericarditis. The hallmark is a persistently elevated right atrial pressure of >10 mmHg or reduction of less than 50% from baseline despite pericardiocentesis. Aetiologies include radiation, infection, malignancy, and autoimmune disease. Case summary A 71-year-old man with a history of atrial fibrillation, obesity, hypertension, obstructive sleep apnoea, managed with continuous positive airway pressure presented with acute pericarditis complicated by pericardial effusion leading to cardiac tamponade. He was diagnosed with ECP after pericardiocentesis and was managed surgically with a pericardial window. Discussion Early detected cases of ECP can be managed by medical therapy. Therapeutic interventions include pericardiocentesis, balloon pericardiostomy, and pericardiectomy. This report describes a case of new-onset congestive heart failure secondary to ECP.

Acute respiratory distress syndrome, characterized by the Berlin criteria, is associated with a high mortality rate. Its treatment includes addressing the underlying etiology, general supportive measures, and achievement of effective oxygenation. New key data indicates that in a subset of patients, noninvasive ventilation techniques can be a therapeutic and equivalent alternative to traditional invasive ventilation. We present a rare case of ARDS triggered by nasal bupropion inhalation and effectively treated with noninvasive positive pressure ventilation resulting in complete resolution.