Clinical hemodynamic evaluation of patients implanted with a fully magnetically levitated left ventricular assist device (HeartMate 3).

BACKGROUND: The HeartMate 3 (HM3) is a Conformiteé Européenne (CE) mark-approved left ventricular assist device (LVAD) with a fully magnetically levitated rotor with features consisting of a wide range of operational speeds, wide flow paths and an artificial pulse. We performed a hemodynamic and echocardiographic evaluation of patients implanted with the HM3 LVAD to assess the speed range for optimal hemodynamic support. METHODS: Sixteen HM3 patients underwent pump speed ramp tests with right heart catheterization (including central venous pressure [CVP], pulmonary artery pressure, pulmonary capillary wedge pressure [PCWP] and blood pressure [BP]) and 3-dimensional echocardiography (3DE). Data were recorded at up to 13 speed settings. Speed changes were in steps of 100 revolutions per minute (rpm), starting at 4,600 rpm and ramping up to 6,200 rpm. RESULTS: Mean original speed was 5,306 ± 148 rpm, with a majority of patients (10 of 16, 62.5%) having normal CVPs and PCWPs at their original rpm settings. Going from lowest to highest speeds, cardiac output improved at the rate of 0.08 ± 0.08 liter/min per 100 rpm (total change 1.25 ± 1.20 liters/min) and PCWP decreased at the rate of -0.48 ± 0.27 mm Hg per 100 rpm (total change -6.13 ± 3.72 mm Hg). CVP and systolic BP did not change significantly with changes in rpm. Left ventricular end-diastolic dimension (LVEDD) decreased at a rate of -0.15 ± 0.09 cm per 100 rpm. Number of rpm was adjusted based on test results to achieve CVPs and PCWPs as close to normal limits as possible, which was feasible in 13 (81.3%) patients. For the remaining 3 patients, medical management was pursued to optimize hemodynamic support. CONCLUSION: Hemodynamic normalization of pressures was achieved in the majority of patients implanted with the HM3 pump within a narrow speed range.

Heart failure is the strongest predictor of acute kidney injury in patients undergoing primary percutaneous coronary intervention for ST-elevation myocardial infarction.

BACKGROUND: ST elevation myocardial infarction (STEMI) patients treated by primary percutaneous coronary intervention (PCI) are at higher risk of acute kidney injury (AKI) than patients undergoing PCI in stable clinical conditions. This fact suggests that mechanisms other than contrast nephrotoxicity are involved. AIM: To evaluate the incidence, risk factors, and consequences of AKI in patients undergoing primary PCI for STEMI in current daily practice. METHODS: Analysis of all consecutive patients who underwent primary PCI over a one-year period. AKI was defined as an increase in serum creatinine ≥ 50% or 26.5 µmol/L (AKIN criteria) from the baseline within 48 h. RESULTS: A total of 202 patients were included. AKI occurred in 25 (12.4%) subjects. Baseline characteristics and in-hospital complications of the patients with and without AKI did not differ significantly except for age (69 ± 13 vs. 62 ± 12; p = 0.003), female gender (48.0% vs. 26.6%; p = 0.035), hypertension (88.0% vs. 62.7%; p = 0.013), left ventricular ejection fraction (40% ± 12% vs. 49% ± 14%; p = 0.002), cardiogenic shock (44.0% vs. 5.1%; p < 0.0001), use of intravenous diuretics (76.0% vs. 26.0%; p < 0.0001), ventricular arrhythmias (24.0% vs. 3.4%; p = 0.001), and in-hospital mortality (24.0% vs. 3.4%; p = 0.001). In multivariate analysis heart failure remained the only independent correlate of AKI. CONCLUSIONS: AKI was an frequent and serious complication of STEMI in patients treated by primary PCI. Heart failure was the strongest predictor of AKI. Other risk factors including contrast medium volume, baseline renal function, diabetes, and age failed to predict AKI.

Prevention of contrast-induced acute kidney injury by theophylline in elderly patients with chronic kidney disease.

Although the optimal strategy for preventing contrast-induced acute kidney injury (CI-AKI) has not yet been established, the current strategy focuses on adequate periprocedural hydration, the use of a low amount of low or iso-osmolar contrast medium, and the application of adjunctive therapies, including hemofiltration, hemodialysis and drugs. Previous trials and meta-analyses concerning the use of the adenosine antagonist theophylline have revealed contradictory results. We sought to evaluate the effect of theophylline in CI-AKI prevention in well-hydrated elderly patients with chronic kidney disease. We therefore conducted a randomized, double-blind, placebo-controlled trial involving 56 patients who had been referred for cardiac coronary angiography and/or angioplasty. 31 of these patients were randomly assigned to 200 mg theophylline IV before the procedure, and 25 to a placebo. The iso-osmolar contrast medium iodixanol was used. The primary endpoint was an increase in serum creatinine at study termination 48 h after contrast medium administration. Baseline characteristics in the placebo and theophylline groups were similar in terms of median age (75 years), estimated glomerular filtration rate (33 ± 10 vs. 33 ± 10 ml/min/1.73 m²; p = 0.87), diabetes mellitus (80 vs. 71%; p = 0.54), and amount of contrast used (94 ± 35 vs. 95 ± 38 ml; p = 0.89). There was no difference in serum creatinine at baseline (2.06 ± 0.59 vs. 2.02 ± 0.45 mg/dl; p = 0.62) or study termination (2.06 ± 0.68 vs. 2.10 ± 0.53; p = 0.79). A prophylactic effect of theophylline was not observed. The incidence of renal impairment following exposure to the contrast medium was low. This fact can be attributed to adequate parenteral hydratation and the use of the minimum amount of contrast medium necessary.