Partial left ventriculectomy: which patients can be expected to benefit?

Background. Although some patients with end-stage heart disease will benefit from a partial left ventriculectomy, no criteria have been found for identifying this group preoperatively. Our experience with partial left ventriculectomy at two institutions—the Texas Heart Institute in Houston, TX, USA, and Dedinje Cardiovascular Institute in Belgrade, Yugoslavia—showed a higher survival rate and better postoperative myocardial function in the Yugoslavian patients.

Methods. We reviewed data from 42 patients (21 at each center) who had idiopathic cardiomyopathy, a left ventricular end-diastolic dimension of more than 70 mm, wall thickness of 1 cm or greater, and New York Heart Association class III or IV symptoms. The only significant difference in preoperative status between the two groups was duration of symptoms. Histologic specimens, blinded as to origin, were graded with regard to myocyte hypertrophy, cytoplasmic vacuolation, and fibrosis. Computer-assisted myocyte and nuclear morphometry was also performed.

Results. Immediately postoperatively, there were no significant intergroup differences in the reduction in cardiac dimension or in corrections of mitral regurgitation. During 6-month follow-up, however, the Texas Heart Institute patients had a lower cardiac index (1.8 versus 3.0 L·min⁻¹·m⁻²; p = 0.001) and left ventricular ejection fraction (24% versus 34%; p = 0.006) than the Dedinje Cardiovascular Institute patients. The Texas Heart Institute patients differed from the Dedinje Cardiovascular Institute patients in the degree of severe or moderate changes in myocyte hypertrophy (90% versus 29%; p = 0.0003) and fibrosis (71% versus 29%; p = 0.006), as well as in the measurements of median myocyte diameter (35 ± 7 μm versus 27 ± 4 μm; p = 0.0002) and median nuclear size (15 ± 4 μm versus 12 ± 2 μm; p = 0.0029).

Conclusions. In the Texas Heart Institute patients, the significant intergroup difference in clinical outcome may have been related to increased myocyte hypertrophy and fibrosis. Further studies should be performed to determine the usefulness of these criteria in selecting patients for partial left ventriculectomy.     

Extracorporeal CO2 removal as bridge to lung transplantation in life‐threatening hypercapnia

In patients awaiting lung transplantation (LTX), adequate gas exchange may not be sufficiently achieved by mechanical ventilation alone if acute respiratory decompensation arises. We report on 20 patients with life‐threatening hypercapnia who received extracorporeal CO₂ removal (ECCO2‐R) by means of the interventional lung assist (ILA®, Novalung) as bridge to LTX. The most common underlying diagnoses were bronchiolitis obliterans syndrome, cystic fibrosis, and idiopathic pulmonary fibrosis, respectively. The type of ILA was pumpless arteriovenous or pump‐driven venovenous (ILA activve®, Novalung) in 10 patients each. ILA bridging was initiated in 15 invasively ventilated and five noninvasively ventilated patients, of whom one had to be intubated prior to LTX. Hypercapnia and acidosis were effectively corrected in all patients within the first 12 h of ILA therapy: PaCO₂ declined from 109 (70–146) to 57 (45–64) mmHg, P < 0.0001; pH increased from 7.20 (7.06–7.28) to 7.39 (7.35–7.49), P < 0.0001. Four patients were switched to extracorporeal membrane oxygenation due to progressive hypoxia or circulatory failure. Nineteen patients (95%) were successfully transplanted. Hospital and 1‐year survival was 75 and 72%, respectively. Bridging to LTX with ECCO2‐R delivered by arteriovenous pumpless or venovenous pump‐driven ILA is feasible and associated with high transplantation and survival rates.     

Prognostic value of hemodynamic vs big endothelin measurements during long-term IV therapy in advanced heart failure patients

STUDY OBJECTIVE: To compare hemodynamics and plasma big endothelin levels in patients awaiting heart transplantation who are receiving continuous IV therapy, and to establish their respective potency for predicting future cardiac events. DESIGN: A randomized, prospective trial of ambulatory continuous treatment with IV prostaglandin E(1) (PGE(1)) vs dobutamine. A subanalysis was conducted of all patients who completed 4 weeks of follow-up in regard to treatment effects on hemodynamics and big endothelin plasma levels. PATIENTS: Thirty-two listed heart transplant candidates who were refractory to oral treatment, 21 patients who were receiving PGE(1), and 11 patients receiving dobutamine. MEASUREMENTS AND RESULTS: Hemodynamics and plasma big endothelin levels were measured at baseline and after 4 weeks. The cardiac index increased significantly (PGE(1) group, 1.7 +/- 0.4 vs 2.5 +/- 0.6 L/min/m(2); dobutamine group, 1.8 +/- 0.3 vs 2.3 +/- 0.6 L/min/m(2); p < 0.05), whereas the systemic vascular resistance index (SVRI) decreased significantly only in the PGE(1) group (3,352 +/- 954 vs 2,178 +/- 519 dyne. s. cm(-5)/m(2); p < 0. 05). The plasma big endothelin level decreased significantly (PGE(1) group, 7.6 +/- 3.1 vs 4.7 +/- 2.6 fmol/mL; dobutamine group, 6.5 +/- 3.7 vs 5.0 +/- 2.6 fmol/mL; p < 0.01 for the time effect). Plasma big endothelin (beta = 0.393; chi(2) = 10.8; p = 0.001) and SVRI (beta = 0.003; chi(2) = 6.9; p < 0.01), both measured after 4 weeks of continuous treatment, were the only independent predictors of future outcome. CONCLUSION: Continuous treatment over 4 weeks with either PGE(1) or dobutamine in patients awaiting heart transplantation yields an improved hemodynamic state accompanied by a reduction of increased big endothelin levels. Plasma big endothelin measured after 4 weeks of continuous therapy provides prognostic information about future outcome.     

HLA-A, -B, -C, -DRB1 and -DQB1 allele and haplotype frequencies in the Serbian population

This study provides the first published detailed analysis of five loci polymorphisms as well as reports of two, three and five loci haplotype frequencies in the Serbian population in a sample of 1992 volunteer bone marrow donors recruited from different part of the country. Typing was performed by PCR SSO method combined with PCR SSP techniques to resolve ambiguities. In total, 16 HLA-A, 28 HLA-B, 14 HLA-C, 13 HLA-DRB1 and 5 HLA-DQB1 allelic groups were identified. The most frequent in allele groups are HLA-A^∗02 (29.5%), HLA-A^∗01 (14.2%), HLA-B^∗35 (13.1%), HLA-B^∗51 (12.8%), HLA-C^∗07 (24.8%), HLA-DRB1^∗11 (16.9%), HLA-DRB1^∗13 (13.2%), HLA-DQB1^∗03 (33.3%) and DQB1^∗05 (33.0%). The most frequent three- and five-loci haplotypes were A^∗01-B^∗08-DRB1^∗03 (5.9%) and A^∗02-B^∗18-DRB1^∗11 (1.9%), A^∗01-B^∗08-C^∗07-DRB1^∗03-DQB1^∗02 (6.6%) followed by A^∗02-B^∗18-C^∗07-DRB1^∗11-DQB1^∗03 (2.5%), then A^∗33-B^∗14-C^∗08-DRB1^∗01-DQB1^∗05 and A^∗02-B^∗35-C^∗04-DRB1^∗16-DQB1^∗05 (2.2% both), respectively. The results of cluster analysis showed that the Serbian population is closely related to the populations living in central Balkan and neighboring European regions. The level of allelic diversity found in this study are relevant to facilitate searching for unrelated matched donor and provide a healthy control population from our region that should be useful in the future disease association study.     

Sleep-dependent changes in the coupling between heart period and arterial pressure in newborn lambs

This study assessed whether sleep-dependent changes in the relationship between heart period (HP) and mean arterial pressure (MAP) occur in newborn life. Electrodes for electrocorticographic, electromyographic, and electrooculographic monitoring and an arterial catheter for blood pressure recordings were implanted in 11 newborn lambs. HP and MAP beat-to-beat values were computed from 120-s blood pressure recordings during quiet wakefulness, active sleep, and quiet sleep. For each recording, the time shift at which the maximum of the HP versus MAP cross-correlation function was attained was identified. For each lamb and wake-sleep state, an average correlation coefficient was then computed corresponding to the median value of such time shifts. The maximum of the cross-correlation function was attained with HP lagging behind MAP. The corresponding mean correlation coefficient was significantly higher in quiet sleep (0.51 +/- 0.05) than either in quiet wakefulness (0.31 +/- 0.05) or in active sleep (0.29 +/- 0.03). Sleep-related differences in the correlation between HP and MAP were maintained after HP and MAP data were low-pass filtered at 0.3 Hz to remove their fast ventilatory oscillations. In conclusion, data indicate that the relationship between spontaneous fluctuations in HP and those in MAP is sleep-state dependent in newborn lambs. A positive HP versus MAP correlation with HP lagging behind MAP is consistent with baroreflex control of HP. Heart rhythm thus may be more tightly controlled by the baroreceptor reflex and less dependent on central autonomic commands in quiet sleep than either in quiet wakefulness or in active sleep.     

Extracorporeal membrane oxygenation in adult patients with hematologic malignancies and severe acute respiratory failure

Introduction

Acute respiratory failure (ARF) is the main reason for intensive care unit (ICU) admissions in patients with hematologic malignancies (HMs). We report the first series of adult patients with ARF and HMs treated with extracorporeal membrane oxygenation (ECMO).

Methods

This is a retrospective cohort study of 14 patients with HMs (aggressive non-Hodgkin lymphoma (NHL) n = 5; highly aggressive NHL, that is acute lymphoblastic leukemia or Burkitt lymphoma, n = 5; Hodgkin lymphoma, n = 2; acute myeloid leukemia, n = 1; multiple myeloma, n = 1) receiving ECMO support because of ARF (all data as medians and interquartile ranges; age, 32 years (22 to 51 years); simplified acute physiology score II (SAPS II): 51 (42 to 65)). Etiology of ARF was pneumonia (n = 10), thoracic manifestation of NHL (n = 2), sepsis of nonpulmonary origin (n = 1), and transfusion-related acute lung injury (n = 1). Diagnosis of HM was established during ECMO in four patients, and five first received (immuno-) chemotherapy on ECMO.

Results

Before ECMO, the PaO₂/FiO₂ ratio was 60 (53 to 65), (3.3 to 3.7). Three patients received venoarterial ECMO because of acute circulatory failure in addition to ARF; all other patients received venovenous ECMO. All patients needed vasopressors, and five needed hemofiltration. Thrombocytopenia occurred in all patients (lowest platelet count was 20 (11 to 21) G/L). Five major bleeding events were noted. ECMO duration was 8.5 (4 to 16) days. ICU and hospital survival was 50%. All survivors were alive at follow-up (36 (10 to 58) months); five patients were in complete remission, one in partial remission, and one had relapsed.

Conclusions

ECMO therapy is feasible in selected patients with HMs and ARF and can be associated with long-term disease-free survival.