Ilia Shochat

Usefulness of Lung Impedance-Guided Pre-Emptive Therapy to Prevent Pulmonary Edema During ST-Elevation Myocardial Infarction and to Improve Long-Term Outcomes

Patients sustaining an ST-segment elevation myocardial infarction (STEMI) frequently develop pulmonary congestion or pulmonary edema (PED). We previously showed that lung impedance (LI) threshold decrease of 12% to 14% from baseline during admission for STEMI marks the onset of the transition zone from interstitial to alveolar edema and predicts evolution to PED with 98% probability. The aim of this study was to prove that pre-emptive LI-guided treatment may prevent PED and improve clinical outcomes. Five hundred sixty patients with STEMI and no signs of heart failure underwent LI monitoring for 84 ± 36 hours. Maximal LI decrease throughout monitoring did not exceed 12% in 347 patients who did not develop PED (group 1). In 213 patients LI reached the threshold level and, although still asymptomatic (Killip class I), these patients were then randomized to conventional (group 2, n = 142) or LI-guided (group 3, n = 71) pre-emptive therapy. In group 3, treatment was initiated at randomization (LI = -13.8 ± 0.6%). In contrast, conventionally treated patients (group 2) were treated only at onset of dyspnea occurring 4.1 ± 3.1 hours after randomization (LI = -25.8 ± 4.3%, p <0.001). All patients in group 2 but only 8 patients in group 3 (11%) developed Killip class II to IV PED (p <0.001). Unadjusted hospital mortality, length of stay, 1-year readmission rate, 6-year mortality, and new-onset heart failure occurred less in group 3 (p <0.001). Multivariate analysis adjusted for age, left ventricular ejection fraction, risk factors, peak creatine kinase, and admission creatinine and hemoglobin levels showed improved clinical outcome in group 3 (p <0.001). In conclusion, LI-guided pre-emptive therapy in patients with STEMI decreases the incidence of in-hospital PED and results in better short- and long-term outcomes.

A novel radiological score to assess lung fluid content during evolving acute heart failure in the course of acute myocardial infarction

Background: Monitoring of lung fluid content (LFC) in order to predict acute heart failure (AHF) during acute myocardial infarction (AMI) is an unmet challenge. Aim: To evaluate in AMI patients the ability of proposed radiological score (RS), which is the sum of selected radiological signs of congestion, to reflect correctly LFC, as assessed with repeat physical examinations and lung impedance (LI) measurements. Methods: Chest X-rays were taken at baseline, when rales were detected, whenever indicated, and at conclusion of monitoring. RS grading for LFC assessment was: RS = 0–1 for normal X-ray, RS = 2–4 for interstitial congestion, and RS values of 5–6, 7–8 and 9–10 signified mild, moderate and severe alveolar edema, respectively. Results: 624 AMI patients without AHF at baseline were monitored (94 ± 42 h). 476 patients (76%) with baseline RS of 0.3 ± 0.5 did not develop AHF. Overt AHF developed in 148 patients (24%) during monitoring; baseline RS (0.6 ± 0.8) reached 5.4 ± 0.7, 7.0 ± 0.8, and 9.8 ± 0.5 at the stages of mild, moderate, and severe alveolar edema, respectively. AHF resolved with treatment. RS decreased to 1.5 ± 1.3 (P < 0.01) and correlated with physical examination (r = 0.6, P < 0.01) and LI (r = −0.9, P < 0.01). Conclusion: RS correlated well with findings on physical examination during AHF and closely correlated with LI.

EVALUATION OF THE EFFECTIVENESS OF IN-HOSPITAL TREATMENT OF CHRONIC HEART FAILURE PATIENTS DURING EXACERBATION BY NON-INVASIVE NET LUNG IMPEDANCE MONITORING DURING ADMISSION

methods: CHF patients were monitored by a device that derives the net lung impedance (LI) from measured trans-thoracic impedance. This device is 25-fold more sensitive than existing ones. A decreasing LI reflects accumulation of lung fluid. Changes in the clinical status of patients and LI were recorded at each monthly outpatient visit. On the basis of LI measurements, clinical assessment, and chest X-ray, the optimal LI was determined for each patient. LI changes from this value are represented as percentage change,

LUNG IMPEDANCE-GUIDED PREEMPTIVE TREATMENT OF CHRONIC HEART FAILURE PATIENTS IN THE OUTPATIENT CLINIC DECREASES HOSPITALIZATIONS FOR ACUTE HEART FAILURE AND IMPROVES SURVIVAL

Results: 163 CHF patients (72±10 years) at NYHA II/III/IV (60/73/30) were randomized to LI-guided preemptive treatment (Group 1, n=82) or to conventional therapy administered by clinical evaluation (Group 2, n=81) according to current guidelines. A LI decrease >15% from baseline was used to initiate early preventive therapy since it has been shown previously that decompensation begins at this level of LI decrease. LVEF and NT-proBNP in groups 1 and 2 at study onset were 22±7%, 5714±2421 pg/ml, and 22±6% and 5752±2501 pg/ml, respectively (p=NS). Rate of re-hospitalizations was lower in group 1 (0.57 vs. 1.02/per patients per year, p<0.01). More patients in group 2 were hospitalized for AHF during the follow up period than in group 2 (45 vs.32%, p=0.08). During follow up period cardiovascular mortality in group 1 was lower than in group 2 (11 vs. 24, p<0.01, respectively). As a result of the higher mortality in group 2, follow up time was longer in group 1 (30.7±25.5 vs. 20.7±14.7 months, p<0.01).