Muscle thickness correlates to muscle cross-sectional area in the assessment of strength training-induced hypertrophy

Muscle thickness (MT) measured by ultrasound has been used to estimate cross-sectional area (measured by CT and MRI) at a single time point. We tested whether MT could be used as a valid marker of MRI determined muscle anatomical cross-sectional area (ACSA) and volume changes following resistance training (RT). Nine healthy, young, male volunteers (24 ± 2 y.o., BMI 24.1 ± 2.8 kg/m² ) had vastus lateralis (VL) muscle volume (VOL) and ACSA_mid (at 50% of femur length, FL) assessed by MRI, and VL MT measured by ultrasound at 50% FL. Measurements were taken at baseline and after 12 weeks of isokinetic RT. Differences between baseline and post-training were assessed by Student's paired t test. The relationships between MRI and ultrasound measurements were tested by Pearson's correlation. After RT, MT increased by 7.5 ± 6.1% (P < .001), ACSA_mid by 5.2 ± 5% (P < .001), and VOL by 5.0 ± 6.9% (P < .05) (values: means ± SD). Positive correlations were found, at baseline and 12 weeks, between MT and ACSA_mid (r = .82, P < .001 and r = .73, P < .001, respectively), and between MT and VOL (r = .76, P < .001 and r = .73, P < .001, respectively). The % change in MT with training was correlated with % change in ACSA_mid (r = .69, P < .01), but not % change in VOL (r = .33, P > .05). These data support evidence that MT is a reliable index of muscle ACSA_mid and VOL at a single time point. MT changes following RT are associated with parallel changes in muscle ACSA_mid but not with the changes in VOL, highlighting the impact of RT on regional hypertrophy.

Training-induced changes in structural and mechanical properties of the patellar tendon are related to muscle hypertrophy but not to strength gains

To obtain a better understanding of the adaptations of human tendon to chronic overloading, we examined the relationships between these adaptations and the changes in muscle structure and function. Fifteen healthy male subjects (20+/-2 yr) underwent 9 wk of knee extension resistance training. Patellar tendon stiffness and modulus were assessed with ultrasonography, and cross-sectional area (CSA) was determined along the entire length of the tendon by using magnetic resonance imaging. In the quadriceps muscles, architecture and volume measurements were combined to obtain physiological CSA (PCSA), and maximal isometric force was recorded. Following training, muscle force and PCSA increased by 31% (P<0.0001) and 7% (P<0.01), respectively. Tendon CSA increased regionally at 20-30%, 60%, and 90-100% of tendon length (5-6%; P<0.05), and tendon stiffness and modulus increased by 24% (P<0.001) and 20% (P<0.01), respectively. Although none of the tendon adaptations were related to strength gains, we observed a positive correlation between the increase in quadriceps PCSA and the increases in tendon stiffness (r=0.68; P<0.01) and modulus (r=0.75; P<0.01). Unexpectedly, the increase in muscle PCSA was inversely related to the distal and the mean increases in tendon CSA (in both cases, r=-0.64; P<0.05). These data suggest that, following short-term resistance training, changes in tendon mechanical and material properties are more closely related to the overall loading history and that tendon hypertrophy is driven by other mechanisms than those eliciting tendon stiffening.

Central venous catheter-related complications in children with oncological/hematological diseases: an observational study of 418 devices

BACKGROUND

The use of indwelling central venous catheters (CVCs) has become commonplace in the management of children undergoing anticancer treatment. Several types of CVC are available, while information on complications observed in children is scarce. We describe the experience of two tertiary care centers in Italy that prospectively followed up three types of CVC used at both institutions over a 30-month period.

PATIENTS AND METHODS

Between January 2000 and May 2002, double-lumen (DL) or single-lumen (SL) Hickman-Broviac (HB) catheters, and single-lumen pressure-activated safety valve (PASV) catheters were used and prospectively evaluated. Four types of possible complication were defined a priori: mechanical, thrombotic, malfunctioning and infectious.

RESULTS

Four hundred and eighteen CVCs (180 SL-HB, 162 DL-HB and 76 PASV) were inserted in 368 children, for a total of 107 012 catheter days at risk of complication. At least one complication occurred while using 169 of the devices (40%): 46% of the DL-HB, 46% of the PASV and 33% of the SL-HB (P=0.02) catheters. Subjects with hematological malignancies or non-malignant diseases had significantly more complications than those with solid tumors (P <0.0001). Overall, 234 complications were documented: 93 infectious [complication rate per 1000 catheter days at risk (CR)=0.87], 84 malfunctioning (CR=0.78), 48 mechanical (CR=0.45) and nine thrombotic (CR=0.08). SL-HB had statistically fewer infectious complications, while PASV had more mechanical complications. In a multivariate regression model, the most significant risk factors for having a CVC complication were hematological disease [relative risk (RR)=3.0; 95% confidence interval (CI) 1.8-4.8] and age <6 years at CVC insertion (RR=2.5; 95% CI 1.5-4.1). As for the type of CVC, compared with SL-HB, the DL-HB catheter had a statistically significant two-fold increased risk of any complication (RR=2.1; 95% CI 1.2-3.6), while the PASV catheter had a borderline RR of 1.8 (95% CI 1.0-3.6). Analysis by tumor type showed a higher risk of any kind of complication in patients with solid malignancies who had received a DL-HB catheter as compared with an SL-HB catheter (RR=7.2; 95% CI 2.8-18.7).

CONCLUSIONS

CVCs may cause complications in up to 40% of patients, with type of CVC, underlying disease and patient age being the three main factors that affect the incidence of CVC-related complications. SL-HB catheters have the best performance.

Transdermal progesterone cream for vasomotor symptoms and postmenopausal bone loss

OBJECTIVE

To determine effectiveness of transdermal progesterone cream for controlling vasomotor symptoms and preventing postmenopausal bone loss.

METHODS

We randomly assigned 102 healthy women within 5 years of menopause to transdermal progesterone cream or placebo. Study subjects and investigators were masked until data analysis was completed. An initial evaluation included complete history, physical examination, bone mineral density determination, and serum studies (TSH, FSH, lipid profile, and chemistry profile). Subjects were instructed to apply a quarter teaspoon of cream (containing 20 mg progesterone or placebo) to the skin daily. Each woman received daily multivitamins and 1200 mg of calcium and were seen every 4 months for review of symptoms. Bone scans and serum chemistries were repeated after 1 year.

RESULTS

Thirty of the 43 (69%) in the treatment group and 26 of the 47 (55%) in the placebo group complained initially of vasomotor symptoms. Improvement or resolution of vasomotor symptoms, as determined by review of weekly symptom diaries, was noted in 25 of 30 (83%) treatment subjects and five of 26 (19%) placebo subjects (P < .001). However, the number of women who showed gain in bone mineral density exceeding 1.2% did not differ (alpha = .05, power of 80%).

CONCLUSION

Although we found no protective effect on bone density after 1 year, we did see a significant improvement in vasomotor symptoms in the treated group.

Nonmedical costs to patients and their families associated with outpatient chemotherapy

One hundred thirty-nine patients receiving outpatient chemotherapy kept diaries of nonmedical expenses resulting from their disease and its treatment. Diaries were kept for both treatment and nontreatment weeks. Results showed that the mean cost to patients and their families for treatment weeks was $72.81, and for nontreatment weeks it was $45.88. Approximately 45% of these costs were out-of-pocket expenses, and 55% were wages lost. Transportation and food were the largest out-of-pocket expenses. Patients living at greater distance from treatment had higher out-of-pocket costs, and younger patients reported more wages lost. Fourteen percent of the patients were estimated to be spending more than 50% of their weekly incomes on nonmedical expenses, and these patients were found largely in the lower-income categories. A method is proposed for using these data to estimate total nonmedical expenses for different treatment regimens, and also for estimating cancer patients' total nonmedical costs nationally.

Early termination of treatment in personality disorder treated in a psychotherapy hospital. Quantitative and qualitative study

BACKGROUND

Factors underlying premature discontinuation of psychosocial in-patient treatment are still unclear.

AIMS

Investigation of early discontinuation of specialised in-patient psychosocial treatment in a sample of people with personality disorder.

METHOD

Out of 134 consecutive admissions to the Cassel Hospital, 42 early drop-outs and 92 patients who remained were compared on demographic and clinical variables. Early drop-outs were invited for in-depth interviews, to explore their hospital experiences.

RESULTS

The early drop-out group and the group which remained showed significant differences in occupational status, borderline personality disorder (BPD) and the treatment programme to which they were allocated. All three independent variables predicted early discontinuation of treatment. The qualitative analysis of interview transcripts identified significant problems in institutional dimensions.

CONCLUSIONS

Important subjects and process variables contributing to early drop-out in people with personality disorder were identified, with potential implications for clinical practice.

Validation of the Composite Autonomic Symptom Score 31 (COMPASS 31) for the assessment of symptoms of autonomic neuropathy in people with diabetes

AIM

To validate the Composite Autonomic Symptom Score (COMPASS) 31, in its Italian version, for the diagnosis of diabetic cardiovascular autonomic neuropathy in a clinic-based, single-centre study.

METHODS

A total of 73 participants with diabetes (age 55 ± 14 years) completed the COMPASS 31 questionnaire before undergoing cardiovascular autonomic neuropathy and diabetic polyneuropathy assessment according to cardiovascular reflex tests, neuropathic symptoms and signs, and vibration and thermal thresholds.

RESULTS

The COMPASS 31 total weighted score differed between participants with and without cardiovascular autonomic neuropathy (29.9 ± 19.5 vs 16.1 ± 14.7; P = 0.003) and with and without diabetic polyneuropathy (28.9 ± 19.1 vs 12.7 ± 11.3; P < 0.0001). It was related to cardiovascular reflex tests score (rho = 0.38, P = 0.0013) as well as diabetic polyneuropathy symptoms (rho=0.61, P < 0.0001) and signs scores (rho = 0.49, P < 0.0001). Receiver-operating curve analysis showed a fair diagnostic accuracy of total score for cardiovascular autonomic neuropathy (area under the curve 0.748 ± 0.068, 95% CI 0.599-0.861) and diabetic polyneuropathy (area under the curve 0.742 ± 0.061, 95% CI 0.611-0.845). The best score thresholds were 16 for early cardiovascular autonomic neuropathy (sensitivity 75.0%, specificity 64.9%, positive predictive value 37.5% and negative predictive value 90.2%), and 17 for both confirmed cardiovascular autonomic neuropathy and diabetic polyneuropathy (sensitivity 70.0% and 65.5%, respectively; specificity 66.7% and 79.5%, respectively; positive predictive value 25.0% and 67.9%, respectively; and negative predictive value 93.0% and 77.8%, respectively). COMPASS 31 had a good internal consistency according to Cronbach's α coefficient of 0.73.

CONCLUSIONS

COMPASS 31 can represent a valid, easy-to-use, quantitative assessment tool for autonomic symptoms in diabetic neuropathy, with a fair diagnostic accuracy for both cardiovascular autonomic neuropathy and diabetic polyneuropathy.

Rapid detection of mecA-positive and mecA-negative coagulase-negative staphylococci by an anti-penicillin binding protein 2a slide latex agglutination test

A rapid slide latex agglutination (LA) test, MRSA-Screen (Denka Seiken Co., Niigata, Japan), which detects PBP 2a, was tested for its ability to differentiate between mecA-positive and -negative coagulase-negative staphylococci. A total of 463 isolates from 13 species were included in the study. The mecA gene was detected by PCR, and the oxacillin MIC was determined by the agar dilution method according to the guidelines of the National Committee for Clinical Laboratory Standards (NCCLS). The LA test was performed with oxacillin-induced isolates. The true-positive and true-negative results were defined on the basis of the presence or the absence of the mecA gene. By PCR, 251 isolates were mecA positive and 212 were mecA negative. The sensitivities, specificities, and positive and negative predictive values for the LA test compared to the NCCLS breakpoint for oxacillin resistance (>/=0.5 mg/liter) were as follows: for the LA test, 100, 99.5, 99.6, and 100%, respectively; for the NCCLS breakpoint, 100, 60.8, 75.1, and 100%, respectively. One hundred twenty-five mecA-positive isolates were also tested by the LA test without induction of PBP 2a; only 72 (57.6%) gave a positive result and required 3 to 15 min for reaction. With induction, all 251 isolates were positive within 3 min. The LA test was reliable in classifying mecA-negative isolates, but it classified isolates for which the oxacillin MIC was >/=0.5 mg/liter as oxacillin susceptible. For the reliable detection of oxacillin resistance by the MRSA-Screen in coagulase-negative staphylococci, induction of the mecA gene appears to be necessary.

Geriatric nutritional risk index as a nutritional and survival risk assessment tool in stable outpatients with systolic heart failure

BACKGROUND AND AIMS

Malnutrition is frequent in heart failure (HF). However, the best tool for evaluating malnutrition in geriatric patients with HF with reduced ejection fraction (HFrEF) is unknown. This study aimed to evaluate the incremental prognostic value of the geriatric nutritional risk index (GNRI) in stable geriatric outpatients with HFrEF compared with a clinical/laboratory prognostic model.

METHODS AND RESULTS

A total of 143 outpatients with HFrEF, aged >65 years, a LVEF <40%, and who were stable and on optimal therapy were studied. Follow-up lasted 3 years. The outcome was all-cause death. The GNRI was calculated as follows: [(1.489 × serum albumin (g/L)) + (41.7 × (current body weight/ideal weight)]. The 3-year death rate was 36.4% and 16 (11.2%) patients were at risk of malnutrition (GNRI ≤98). Deceased patients had a lower GNRI (113.6 ± 9.1 vs. 105.6 ± 9.2; p < 0.001) than did survivors. Greater values of the GNRI (hazard ratio = 0.93, 95% confidence interval [CI] = 0.90-0.95; p < 0.001) and GNRI >98 (hazard ratio = 0.29, 95% CI 0.15-0.57; p < 0.001) were associated with better survival. These factors remained significant after adjustment of significant confounders. The GNRI was a better discriminator of death than weight and albumin. Adding the GNRI to the clinical/laboratory predictor survival model significantly increased the c-statistics from 0.93 to 0.95 (p < 0.001) and the chi-square likelihood ratio test from 106.15 to 119.9.

CONCLUSION

The risk of malnutrition, as assessed by the GNRI, in stable geriatric outpatients with HFrEF is a strong independent predictor of survival. The GNRI adds significant prognostic information to the clinical/laboratory model.

BRCA1 mutations and polymorphisms in a hospital-based consecutive series of breast cancer patients from Apulia, Italy

INTRODUCTION

Hereditary breast cancer has been partly attributed to germline mutations in the BRCA1 gene that are deleterious for BRCA1 protein activity. This paper analyzes the incidence and characteristics of detectable BRCA1 mutations and polymorphisms in a hospital-based consecutive series of breast cancer patients from southern Italy to investigate the incidence and the association of these molecular alterations with breast cancer biology and family history.

METHODS

One hundred cases with familial characteristics were selected from a consecutive series of 511 patients with a first diagnosis of breast cancer. DNA from peripheral blood was screened for whole BRCA1 gene mutations utilizing dHPLC as a pre-screening analysis and automatic DNA sequencing for the identification of specific alterations.

RESULTS

In the overall series of 511 patients, 100 had a family history of breast cancer and were investigated for BRCA1 mutations. Two types of BRCA1 mutations were identified, 5382insC in six cases and 4566delA in one case. The 5382insC mutation was present in two out of six cases with ovarian cancer while 4566delA in one case of male cancer. The most frequent missense polymorphisms were E1038G, P871L, K1183R in exon 11, S1613G, M1652I in exon 16 and D1778G in exon 22. Confirming what found in previous studies, patients in whom pathological BRCA1 mutations were detected had early-onset breast cancer (p=0.05), positive nodal status (p=0.05), lower ER (p=0.02) and PgR (p=0.01) content. Interestingly, the K1183R polymorphism and, less strongly, S1613G polymorphism were associated to mutational risk (K1183R: OR 0.1 p=0.03; S1613G: OR 2.7 p=0.08).

CONCLUSION

Mutations in the BRCA1 gene are frequent also in our consecutive series of patients from southern Italy. An association between two detected single nucleotide polymorphisms (SNPs) and BRCA1 mutational risk was ascertained. Finally, we confirm the fact that peculiar clinical-pathological features seem to characterize patients with a family history of breast cancer and BRCA1 alterations.

Nosocomial infections in pediatric cardiac surgery, Italy

OBJECTIVE

To evaluate the incidence of nosocomial infection (NI) in pediatric patients who received cardiothoracic surgery and to identify possible associated risk factors.

DESIGN

Prospective observational study.

SETTING

The cardiac surgery and cardiac intensive care units at the Regina Margherita Children's Hospital, Turin, Italy.

PATIENTS

All patients who underwent surgery from July 20, 1998, to July 19, 1999, were enrolled, except patients with operative catheterization only.

METHODS

Clinical data were collected daily from July 20, 1998, to July 19, 1999. NIs were diagnosed according to US Centers for Disease Control and Prevention criteria.

RESULTS

104 patients were included in the present study, 80 (76.9%) of whom underwent extracorporeal circulation. The NI ratio was 48.1% (50/104); the percentage of patients with NI was 30.8% (32/104): 23.1% developed one infection, 7.7% two or more. The rate of NI was 2.17 per 100 days of hospitalization (50/2,304). The most common pathogen was Pseudomonas aeruginosa. Important risk factors were length of preoperative admission >5 days, total length of admission >10 days, open chest during postoperative phase, and cyanotic heart disease. There was a significant association between sepsis and central venous catheterization for 3 days or more. Rate of sepsis was 19 per 1,000 catheter days (16/852).

CONCLUSION

NIs represent a frequent complication for children who undergo heart surgery. Based on our data, we suggest decreasing the preoperative stay as much as possible. The higher NI incidence in patients with an open chest postoperatively suggests that an alternative antibiotic strategy should be considered for these patients.

Antisense-mediated inhibition of the bcl-2 gene induces apoptosis in human malignant glioma

BACKGROUND

The bcl-2 protooncogene represses a number of cellular apoptotic pathways and is known to be expressed in increasing amounts in glial tumors of higher malignancy. We tested whether antisense oligonucleotides to the bcl-2 gene would affect glioma cell viability.

METHODS

Antisense oligonucleotides directed to the first six codons of the human bcl-2 gene, and nonsense oligonucleotides as a control, were transfected into malignant glioma cells. Two human Bcl-2 positive glioblastoma cell lines from our tumor bank (Jon52 and Roc) were both transfected in vitro with bcl-2 antisense (AS) and nonsense (NS) oligonucleotides at 1 microm and 5 microm concentrations for 5 and 24 hr. Cell viability was assessed at 2, 4, 5, and 7 days by using an MTT mitogenic assay and by cell counting via direct visualization using a hemocytometer.

RESULTS

There was up to a log-fold decrease in cell growth of the bcl-2 AS treated cells compared to the NS transfected cells for both Roc (p = 0.007 and p = 0.004) and Jon52 (p = 0.02 and p = 0.004) at 5 and 24 hr of transfection. There was as much as 50% cytotoxicity in both glioblastoma cell lines at 1 microm and 5 microm concentrations after 24 hr transfection with AS bcl-2 oligonucleotides (all p < 0.01). Western blot analysis demonstrated a decrease in the expression of the Bcl-2 protein in one cell line, whereas there was a statistically significant increase in the apoptotic index of both cell lines (p < 0.05 by chi square analysis).

CONCLUSIONS

Our results suggest that transfection of human glioma cells with antisense bcl-2 results in an increase in apoptotic death. This provides evidence that Bcl-2 plays a role in tumor progression of glioma by acting as an oncogene, and suggests that inhibition of the bcl-2 gene could have a therapeutic effect.

Health resource utilization of labor induction versus expectant management

BACKGROUND

Although induction of labor of low-risk nulliparous women at 39 weeks reduces the risk of cesarean delivery compared with expectant management, concern regarding more frequent use of labor induction remains, given that this intervention historically has been thought to incur greater resource utilization.

OBJECTIVE

The objective of the study was to determine whether planned elective labor induction at 39 weeks among low-risk nulliparous women, compared with expectant management, was associated with differences in health care resource utilization from the time of randomization through 8 weeks postpartum.

STUDY DESIGN

This is a planned secondary analysis of a multicenter randomized trial in which low-risk nulliparous women were assigned to induction of labor at 39 weeks or expectant management. We assessed resource utilization after randomization in 3 time periods: antepartum, delivery admission, and discharge through 8 weeks postpartum.

RESULTS

Of 6096 women with data available, those in the induction of labor group (n = 3059) were significantly less likely in the antepartum period after randomization to have at least 1 ambulatory visit for routine prenatal care (32.4% vs 68.4%), unanticipated care (0.5% vs 2.6%), or urgent care (16.2% vs 44.3%), or at least 1 antepartum hospitalization (0.8% vs 2.2%, P < .001 for all). They also had fewer tests (eg, sonograms, blood tests) and treatments (eg, antibiotics, intravenous hydration) prior to delivery. During the delivery admission, women in the induction of labor group spent a longer time in labor and delivery (median, 0.83 vs 0.57 days), but both women (P = .002) and their neonates (P < .001) had shorter postpartum stays. Women and neonates in both groups had similar frequencies of postpartum urgent care and hospital readmissions (P > .05 for all).

CONCLUSION

Women randomized to induction of labor had longer durations in labor and delivery but significantly fewer antepartum visits, tests, and treatments and shorter maternal and neonatal hospital durations after delivery. These results demonstrate that the health outcome advantages associated with induction of labor are gained without incurring uniformly greater health care resource use.

Nonequilibrium steady-state fluctuations in actively cooled resonators

We analyze heat and work fluctuations in the gravitational wave detector AURIGA, modeled as a macroscopic electromechanical oscillator in contact with a thermostat and cooled by an active feedback system. The oscillator is driven to a steady state by the feedback cooling, equivalent to a viscous force. The experimentally measured fluctuations are in agreement with our theoretical analysis based on a stochastically driven Langevin system. The asymmetry of the fluctuations of the absorbed heat characterizes the oscillator's nonequilibrium steady state and reveals the extent to which a feedback cooled system departs from equilibrium in a statistical mechanics perspective.

Benign lymph node inclusions

Whether obtained during a radical surgical procedure, or as the only tissue removed in various cancer staging procedures, or as incidental tissue, lymph nodes may yield pivotal histopathologic information relating to further disposition of the patient. Most important are those cases in which lymph node findings are relied upon to establish a diagnosis of malignant disease. The two cases presented here (in addition to the few reports in the literature) represent two heretofore unreported sites of occurrence of such benign inclusions. There is need for an awareness of the occurrence, benign nature, and potentially misleading associations with frequent sites of malignant change in which metastasis to regional lymph nodes is known to occur. Particularly with the growing use of mediastinoscopy the misinterpretation of such benign inclusions could prompt the insitution of incorrect and potentially hazardous therapy or a decision to withhold therapy.

Evaluation of screening and commercial methods for detection of methicillin resistance in coagulase-negative staphylococci

The National Committee for Clinical Laboratory Standards recommends 48 h of incubation by the oxacillin salt agar screen (OSAS) method for the detection of methicillin-resistant coagulase-negative staphylococci (CoNS). An earlier identification of methicillin resistance is desirable. The time to detection of the mecA gene by PCR was compared with the times to detection by OSAS, by the oxacillin disk diffusion (ODD) method, and with MicroScan Gram Positive Combo type 6 panels (MicroScan Inc. Sacramento, Calif.) and Vitek GPS-SA cards (bioMérieux Vitek Inc., Hazelwood, Mo.). The combination of the Vitek card and the ODD method detected 92 of 99 methicillin-resistant strains of CoNS at 24 h; however, 6 mecA-positive strains were phenotypically methicillin susceptible. We conclude that most methicillin-resistant CoNS can be detected and the results can be reported after overnight incubation by a combination of methods.

Recovery of volatile fatty acids from fermentation of sewage sludge in municipal wastewater treatment plants

This work investigated the pilot scale production of short chain fatty acids (SCFAs) from sewage sludge through alkaline fermentation and the subsequent membrane filtration. Furthermore, the impact of the fermentation liquid on nutrient bioremoval was examined. The addition of wollastonite in the fermenter to buffer the pH affected the composition of the carbon source produced during fermentation, resulting in higher COD/NH4-N and COD/PO4-P ratios in the liquid phase and higher content of propionic acid. The addition of wollastonite decreased the capillary suction time (CST) and the time to filter (TTF), resulting in favorable dewatering characteristics. The sludge dewatering characteristics and the separation process were adversely affected from the use of caustic soda. When wollastonite was added, the permeate flux increased by 32%, compared to the use of caustic soda. When fermentation liquid was added as carbon source for nutrient removal, higher removal rates were obtained compared to the use of acetic acid.

Impact of obstructive sleep apnea in recruitment of coronary collaterality during inaugural acute myocardial infarction

BACKGROUND

Obstructive sleep apnea (OSA) may lead to myocardial preconditioning by increasing coronary collateral vessel recruitment in patients with acute coronary occlusion.

AIM

To determine the relationship between the severity of obstructive sleep apnea and coronary collaterality during acute myocardial infarction.

METHODS

This study prospectively included 71 patients with an inaugural myocardial infarction who had undergone a coronary angiography within 24h of onset. All patients underwent an overnight polygraph before discharge and were classified according to the apnea-hypopnea index (AHI). Coronary collaterals were scored by visual analyses and according to the Rentrop grading system.

RESULTS

Mean age was 59±11years and 83% of patients were men. All patients had complete or subtotal occlusion of the infarct-related artery. After the sleep study, patients were divided into two groups: 25 were suffering from OSA (AHI>15/h). Patients with OSA showed better collateral vessel development (Rentrop score≥1) compared to non-OSA patients (68 vs. 41%, P=0.032). AHI was significantly higher in patients with developed coronary collaterals (Rentrop≥1) compared to those without collaterality (17.74±13.2 vs. 12.24±10.9, P=0.025).

CONCLUSION

Coronary collateral development may be increased in OSA patients who are presenting with a first myocardial infarction.