Predicting outcome in ex-premature infants supported with extracorporeal membrane oxygenation for acute hypoxic respiratory failure

OBJECTIVE

To identify predictors of outcome in ex-premature infants supported with extracorporeal membrane oxygenation (ECMO) for acute hypoxic respiratory failure.

METHODS

Retrospective review of ex-premature infants with acquired acute hypoxic respiratory failure requiring ECMO support in the United Kingdom from 1992 to 2001. Review of follow up questionnaires completed by general practitioners and local paediatricians.

RESULTS

Sixty four ex-premature infants (5-10 each year) received ECMO support, despite increased use of advanced conventional treatments over the decade. The most common infective agent was respiratory syncytial virus (85% of cases). Median birth gestation was 29 weeks and median corrected age at the time of ECMO support was 42 weeks. Median ECMO support duration was relatively long, at 229 hours. Survival to hospital discharge and to 6 months was 80%, remaining similar throughout the period of review. At follow up, 60% had long term neurodisability and 79% had chronic pulmonary problems. Of pre-ECMO factors, baseline oxygen dependence, younger age, and inpatient status were associated with non-survival (p < or = 0.05). Of ECMO related factors, patient complications were independently associated with adverse neurodevelopmental outcome and death (p < 0.01).

CONCLUSIONS

Survival rates for ex-premature infants after ECMO support are favourable, but patients suffer a high burden of morbidity during intensive care and over the long term. At the time of ECMO referral, baseline oxygen dependence is the most important predictor of death, but no combination of the factors considered was associated with a mortality that would preclude ECMO support.

Pitfalls of adverse event reporting in paediatric cardiac intensive care

AIMS

To evaluate the pitfalls of incident reporting in a complex medical environment.

METHODS

Retrospective review of 211 incident reports in a paediatric cardiac intensive care unit (CICU). Two adverse event reporting databases were compared: database A (DA), the hospital's official reporting system, is non-anonymous and reports are predominantly made by nurses; database B (DB) is anonymous and reports are submitted by a CICU consultant who collects data from daily ward rounds. Both databases classify adverse events into incident type (drug errors, ventilation, cannulae/indwelling lines, chest drains, blood transfusion, equipment, operational) and severity (0 = no, 1 = minor, 2 = major, 3 = life threatening consequences).

RESULTS

Between 1 April 1998 and 31 July 2001 there were 211 adverse events involving 178 patients (11.87%), among 1500 patients admitted to CICU. A total of 112 incidents were reported in DA, 143 in DB, and 44 in both. In isolation, both databases gave an unrepresentative picture of the true frequency and severity of adverse events. Under-reporting was especially notable for less severe events (grade 0, or near misses)

CONCLUSION

Incident reporting in the medical field is highly variable, and is heavily influenced by profession of the reporters as well as anonymity. When adverse event reporting is based predominantly on the observations of a single professional group, the data are grossly inaccurate.

Cardiac ECMO for biventricular hearts after paediatric open heart surgery

OBJECTIVE

To delineate predictors of hospital survival in a large series of children with biventricular physiology supported with extracorporeal membrane oxygenation (ECMO) after open heart surgery.

RESULTS

81 children were placed on ECMO after open heart surgery. 58% (47 of 81) were transferred directly from cardiopulmonary bypass to ECMO. Hospital survival was 49% (40 of 81) but there were seven late deaths among these survivors (18%). Factors that improved the odds of survival were initiation of ECMO in theatre (64% survival (30 of 47)) rather than the cardiac intensive care unit (29% survival (10 of 34)) and initiation of ECMO for reactive pulmonary hypertension. Important adverse factors for hospital survival were serious mechanical ECMO circuit problems, renal support, residual lesions, and duration of ECMO.

CONCLUSIONS

Hospital survival of children with biventricular physiology who require cardiac ECMO is similar to that found in series that include univentricular hearts, suggesting that successful cardiac ECMO is critically dependent on the identification of hearts with reversible ventricular dysfunction. In our experience of postoperative cardiac ECMO, the higher survival of patients cannulated in the operating room than in the cardiac intensive care unit is due to early effective support preventing prolonged hypoperfusion and the avoidance of a catastrophic cardiac arrest.

Near-fatal grape aspiration with complicating acute lung injury successfully treated with extracorporeal membrane oxygenation

OBJECTIVE

In this report of a near-fatal case of grape aspiration successfully treated with extracorporeal membrane oxygenation (ECMO), we highlight the danger of feeding seedless grapes to young children and demonstrate that ECMO can provide cardiopulmonary support for cases of acquired large-airway disruption and can facilitate therapeutic intervention.

DESIGN

Case report.

SETTING

A tertiary pediatric intensive care unit and ECMO center.

PATIENT

A healthy 14-month-old boy aspirated a seedless grape while playing at home and suffered a cardiopulmonary arrest of 15 mins in duration. He responded to advanced life support with return of cardiac output but developed intractable cardiopulmonary failure secondary to aspirated grape particles and postobstructive pulmonary edema.

INTERVENTIONS

The patient was emergently transferred to the regional ECMO center and placed on venoarterial ECMO. Bronchoscopies were performed in the stable environment provided by ECMO, aspirated particles were removed from the large airways, and lung recovery was facilitated.

MEASUREMENTS AND MAIN RESULTS

End-organ perfusion was restored via ECMO during a period of severe intractable cardiopulmonary failure. Pulmonary recovery occurred during a 6-day ECMO run and was facilitated by therapeutic bronchoscopy. The patient was reviewed 1 yr later and has made a full neurodevelopmental recovery, despite a 15-min out-of-hospital cardiac arrest.

CONCLUSIONS

Aspiration of a seedless grape is a life-threatening event in a small child. This danger is not fully appreciated by parents in the UK. ECMO may be life saving in cases of acquired large-airway disruption resulting in severe cardiopulmonary failure, including foreign body aspiration, as long as end-organ perfusion is maintained.

Impact of junctional ectopic tachycardia on postoperative morbidity following repair of congenital heart defects

OBJECTIVE

To determine the incidence of postoperative junctional ectopic tachycardia (JET), we reviewed 343 consecutive patients undergoing surgery between 1997 and 1999. The impact of this arrhythmia on in-hospital morbidity and our protocol for treatment were assessed.

METHODS

We reviewed the postoperative course of patients undergoing surgery for ventricular septal defect (VSD; n=161), tetralogy of Fallot (TOF; n=114), atrioventricular septal defect (AVSD; n=58) and common arterial trunk (n=10). All patients with JET received treatment, in a stepwise manner, beginning with surface cooling, continuous intravenous amiodarone, and/or atrial pacing if the haemodynamics proved unstable. A linear regression model assessed the effect of these treatments upon hours of mechanical ventilation, and stay on the cardiac intensive care unit (CICU).

RESULTS

Overall mortality was 2.9% (n=10), with three of these patients having JET and TOF. JET occurred in 37 patients (10.8%), most frequently after TOF repair (21.9%), followed by AVSD (10.3%), VSD (3.7%), and with no occurrence after repair of common arterial trunk. Mean ventilation time increased from 83 to 187 h amongst patients without and with JET patients (P<0.0001). Accordingly, CICU stay increased from 107 to 210 h when JET occurred (P<0.0001). Surface cooling was associated with a prolongation of ventilation and CICU stay, by 74 and 81 h, respectively (P<0.02; P<0.02). Amiodarone prolonged ventilation and CICU stay, respectively, by 274 and 275 h (P<0.05; P<0.06).

CONCLUSIONS

Postoperative JET adds considerably to morbidity after congenital cardiac surgery, and is particularly frequent after TOF repair. Aggressive treatment with cooling and/or amiodarone is mandatory, but correlates with increased mechanical ventilation time and CICU stay. Better understanding of the mechanism underlying JET is required to achieve prevention, faster arrhythmic conversion, and reduction of associated in-hospital morbidity.

Sulindac sulfide, but not sulindac sulfone, inhibits colorectal cancer growth

Sulindac sulfide, a metabolite of the nonsteroidal antiinflammatory drug (NSAID) sulindac sulfoxide, is effective at reducing tumor burden in both familial adenomatous polyposis patients and in animals with colorectal cancer. Another sulindac sulfoxide metabolite, sulindac sulfone, has been reported to have antitumor properties without inhibiting cyclooxygenase activity. Here we report the effect of sulindac sulfone treatment on the growth of colorectal carcinoma cells. We observed that sulindac sulfide or sulfone treatment of HCA-7 cells led to inhibition of prostaglandin E2 production. Both sulindac sulfide and sulfone inhibited HCA-7 and HCT-116 cell growth in vitro. Sulindac sulfone had no effect on the growth of either HCA-7 or HCT-116 xenografts, whereas the sulfide derivative inhibited HCA-7 growth in vivo. Both sulindac sulfide and sulfone inhibited colon carcinoma cell growth and prostaglandin production in vitro, but sulindac sulfone had no effect on the growth of colon cancer cell xenografts in nude mice.

Meloxicam inhibits the growth of colorectal cancer cells

Cyclooxygenase-2 has been reported to play an important role in colorectal carcinogenesis. The effects of meloxicam (a COX-2 inhibitor) on the growth of two colon cancer cell lines that express COX-2 (HCA-7 and Moser-S) and a COX-2 negative cell line (HCT-116) were evaluated. The growth rate of these cells was measured following treatment with meloxicam. HCA-7 and Moser-S colony size were significantly reduced following treatment with meloxicam; however, there was no significant change in HCT-116 colony size with treatment. In vivo studies were performed to evaluate the effect of meloxicam on the growth of HCA-7 cells when xenografted into nude mice. We observed a 51% reduction in tumor size after 4 weeks of treatment. Analysis of COX-1 and COX-2 protein levels in HCA-7 tumor lysates revealed a slight decrease in COX-2 expression levels in tumors taken from mice treated with meloxicam and no detectable COX-1 expression. Here we report that meloxicam significantly inhibited HCA-7 colony and tumor growth but had no effect on the growth of the COX-2 negative HCT-116 cells.

Carotid artery pseudoaneurysm as a complication of ECMO

Any pulsatile neck mass after extracorporeal membrane oxygenation (ECMO) must be viewed as a pseudoaneurysm of the carotid artery until proven otherwise. Prompt diagnosis is necessary utilizing ultrasound. Angiography may not be necessary. Carotid artery pseudoaneurysm requires urgent surgical intervention to prevent catastrophic hemorrhage. The utilization of cardiopulmonary bypass may facilitate safe repair.

Early response to inhaled nitric oxide and its relationship to outcome in children with severe hypoxemic respiratory failure

OBJECTIVE

To examine whether the early response to inhaled nitric oxide (iNO) is a measure of reversibility of lung injury and patient outcome in children with acute hypoxemic respiratory failure (AHRF).

DESIGN

Retrospective review study.

SETTING

Pediatric ICUs.

PATIENTS

Thirty infants and children, aged 1 month to 13 years (median, 7 months) with severe AHRF (mean alveolar arterial oxygen gradient of 568+/-9.3 mm Hg, PaO2/fraction of inspired oxygen of 56+/-2.3, oxygenation index [OI] of 41+/-3.8, and acute lung injury score of 2.8+/-0.1). Eighteen patients had ARDS.

INTERVENTIONS

The magnitude of the early response to iNO was quantified as the percentage change in OI occurring within 60 min of initiating 20 ppm iNO therapy. This response was compared to patient outcome data.

MEASUREMENTS AND RESULTS

There was a significant association between early response to iNO and patient outcome (Kendall tau B r=0.43, p < 0.02). All six patients who showed < 15% improvement in OI died; 4 of the 11 patients (36%) who had a 15 to 30% improvement in OI survived, while 8 of 13 (61%) who had a > 30% improvement in OI survived. Overall, 12 patients (40%) survived, 9 with ongoing conventional treatment including iNO, and 3 with extracorporeal support.

CONCLUSIONS

In AHRF in children, greater early response to iNO appears to be associated with improved outcome. This may reflect reversibility of pulmonary pathophysiologic condition and serve as a bedside marker of disease stage.

Extracorporeal support for intractable cardiorespiratory failure due to meningococcal disease

BACKGROUND

Meningococcal disease is still associated with considerable mortality, despite the use of early antibiotics and management in specialised intensive care units, due principally to early refractory myocardial depression and hypotension as well as severe acute respiratory distress syndrome. Extracorporeal membrane oxygenation (ECMO) is a complex technology that uses a modified "heart-lung" machine to provide temporary cardiac and respiratory support. We reviewed the UK and Australian experience of the use of ECMO in patients with refractory cardiorespiratory failure due to meningococcal disease.

METHODS

The records from all 12 known patients supported with ECMO for meningococcal disease in the UK and Australia since 1989 were reviewed.

FINDINGS

12 patients (aged 4 months to 18 years, median 26 months) with meningococcal disease received ECMO over 8 years. In seven patients, ECMO was required early for cardiac support for intractable shock within 36 h of admission to intensive care. In the other five patients, ECMO was indicated for respiratory failure due to severe adult respiratory distress syndrome, which tended to occur later in the disease. The paediatric risk of mortality score ranged from 13 to 40 (median 29, median predicted risk of mortality 72%). Six of the 12 patients required cardiopulmonary resuscitation before ECMO and the other six were deteriorating despite maximal conventional therapy. Overall, eight of the 12 patients survived, with six leading functionally normal lives at a median of 1 year (range 4 months to 4 years) of follow-up.

INTERPRETATION

ECMO might be considered to support patients with intractable cardiorespiratory failure due to meningococcal disease who are not responding to conventional treatment.

Pharmacological control of pulmonary blood flow with inhaled nitric oxide after the fenestrated Fontan operation

BACKGROUND

A transient increase in pulmonary vascular resistance can result in hemodynamic compromise after a Fontan operation. An interatrial fenestration is designed to maintain cardiac output in these circumstances but may result in severe hypoxemia and a vicious circle due to hypoxemia induced pulmonary vasoconstriction. Our aim was to determine whether inhaled nitric oxide (iNO), a selective pulmonary vasodilator, could be used to reduce pulmonary vascular resistance in desaturated patients (SaO2 < or = 85%) after a fenestrated Fontan operation.

METHODS AND RESULTS

Responses to iNO (20 ppm for 15 min) were assessed in 10 consecutive children with SaO2 < or = 85% and compared with 5 with SaO2 > 85% after a fenestrated Fontan operation. Exposure to iNO resulted in a significant increase in SaO2 (from 64 +/- 5% to 82 +/- 2%, P < .01) and reduction in transpulmonary gradient (TPG) (from 12.2 +/- 1 [SEM] to 9.6 +/- 1.1, P < .01) in patients with baseline SaO2 < or = 85%. Baseline saturation was a predictor of response to iNO, with a greater response in those with lower saturations (r = -.86, P < .01). In contrast, no significant effects were noted in PaO2 or TPG (from 122 +/- 46 mm Hg and 8 +/- 1.8 to 123 +/- 43 mm Hg and 7 +/- 1.2, respectively) in patients with baseline SaO2 > 85%.

CONCLUSIONS

iNO improved both oxygenation and TPG in desaturated patients after the fenestrated Fontan operation, possibly by counteracting hypoxemia-induced pulmonary vasoconstriction. A trial of iNO should be considered in clinically unstable desaturated patients after the fenestrated Fontan operation.

Four Patterns of Response to Inhaled Nitric Oxide for Persistent Pulmonary Hypertension of the Newborn

Objective. To determine the clinical role of inhaled nitric oxide (iNO) in the treatment of persistent pulmonary hypertension of the newborn (PPHN).

Study Design. Prospective open observational clinical study.

Setting. A regional cardiac and pediatric intensive care unit.

Methods. Twenty-five consecutive near-term neonates (&gt;35 weeks gestation) with severe PPHN (oxygenation index [OI]&gt; 25) were given a trial of iNO of 20 ppm for 20 minutes. Neonates who showed a greater than 20% improvement in Pao 2 as well as a decrease in the OI to below 40 were defined as responders and continued on this therapy.

Results. Four patterns of response emerged to the iNO therapy: Pattern 1 neonates (n = 2) did not respond to the initial trial of iNO—one survived. Pattern 2 neonates (n = 9) responded to the initial trial of iNO, but failed to sustain this response over 36 hours, as defined by a rise in the OI to &gt;40. Six survived, five with extracorporeal membrane oxygenation. Pattern 3 neonates (n = 11) responded to the initial trial of iNO, sustained this response, and were successfully weaned from iNO within 5 days—all survived to discharge. Pattern 4 neonates (n = 3) responded to the initial trial of iNO, but developed a sustained dependence on iNO for 3 to 6 weeks. All three died and lung histology revealed severe pulmonary hypoplasia and dysplasia. These neonates (pattern 4) not only required iNO for a longer period of time than did the sustained responders (pattern 3), but they required significantly higher doses of iNO during their first 5 days of iNO therapy.

Conclusions. Early responses to iNO may not be sustained. Neonates with pulmonary hypoplasia and dysplasia may have a decreased sensitivity and differing time course of response to iNO when compared with patients who have PPHN in fully developed lungs.

Nitric oxide might reduce the need for extracorporeal support in children with critical postoperative pulmonary hypertension

BACKGROUND

Postoperative pulmonary hypertension is a life-threatening, yet reversible complication of congenital heart operations. Although inhaled nitric oxide (iNO), a selective pulmonary vasodilator, has been shown extensively to improve short-term oxygenation and hemodynamic indices in these patients, its influence on patient outcome has not been evaluated. The purpose of this study was to assess retrospectively whether patients who fulfilled our criteria for extracorporeal life support (ECLS) for critical postoperative pulmonary hypertension still required ECLS after the administration of iNO therapy.

METHODS

Since January 1992, 10 patients (age 3 days to 10 months) fulfilled the criteria at our institution for ECLS for postoperative pulmonary hypertension. Of these, 5 could not be separated from cardiopulmonary bypass because of pulmonary hypertension, and 5 had critical pulmonary hypertension (pulmonary arterial pressure approaching systemic arterial pressure) causing severe cardiopulmonary compromise.

RESULTS

Six of the 10 ECLS candidates had a sustained response to iNO and survived to discharge from the hospital, without the need for rescue ECLS. Three patients still required ECLS after 30 minutes, 4 hours, and 8 hours of beginning iNO because of failing cardiac output, and 2 survived. The remaining patient died after 5 days of iNO therapy, but was no longer a candidate for ECLS because of sepsis and multiorgan system failure.

CONCLUSIONS

Children with critical pulmonary hypertension unresponsive to maximal conventional treatment may be managed successfully with iNO without the need for rescue ECLS. A trial of iNO should therefore be given before the use of ECLS in these patients.

Extracorporeal membrane oxygenation as a bridge to definitive tracheal surgery in children

Extracorporeal membrane oxygenation was used as a bridge for three infants with complicated long segment congenital tracheal stenosis to tracheal homograft transplantation with cadaveric tracheal homograft and for one child, with an extensive traumatic tracheal laceration caused by aspiration of a sharp foreign body, to definitive tracheal repair. In all four cases mechanical ventilation was impossible and death almost certain without extracorporeal membrane oxygenation.

Nitric oxide is superior to prostacyclin for pulmonary hypertension after cardiac operations

BACKGROUND

Severe pulmonary hypertension is still a cause of morbidity and mortality in children after cardiac operations. The objective of this study was to compare the vasodilator properties of inhaled nitric oxide, a novel pulmonary vasodilator, and intravenous prostacyclin in the treatment of severe postoperative pulmonary hypertension.

METHODS

Thirteen children (aged 3 days to 12 months) with severe pulmonary hypertension after cardiac operations were given inhaled nitric oxide (20 ppm x 10 minutes) and intravenous prostacyclin (20 ng.kg-1.min-1 x 10 minutes) in a prospective, randomized cross-over study.

RESULTS

Both nitric oxide and prostacyclin resulted in a reduction in pulmonary arterial pressure, although the mean pulmonary arterial pressure was significantly lower during nitric oxide therapy (28.5 +/- 2.9 mm Hg) than during prostacyclin therapy (35.4 +/- 2.1 mm Hg; p < 0.05). The mean pulmonary to systemic arterial pressure ratio was also significantly lower during nitric oxide than prostacylin administration (0.46 +/- 0.04 versus 0.68 +/- 0.05; p < 0.01), due mainly to only prostacyclin lowering systemic blood pressure.

CONCLUSIONS

Inhaled nitric oxide was a more effective and selective pulmonary vasodilator than prostacyclin and should be considered as the preferred treatment for severe postoperative pulmonary hypertension.

Role of echocardiography/Doppler in cardiogenic shock: silent mitral regurgitation

Two cases of cardiogenic shock and pulmonary edema due to acute, severe, silent mitral regurgitation are discussed. The mechanism for the mitral regurgitation was papillary muscle rupture in the setting of acute myocardial infarction. Echocardiography established the presence, severity, and cause of the mitral regurgitation and the associated hyperdynamic left ventricular function in the setting of cardiogenic shock. Transesophageal echocardiography is excellent for assessing the mitral valve in critically ill patients in whom transthoracic echocardiography may be inadequate or misleading. This allowed for emergency mitral valve replacement without prolonged attempts at medical stabilization.

Transesophageal echocardiography to improve positioning of radiofrequency ablation catheters in left-sided Wolff-Parkinson-White syndrome

Two patients with the Wolff-Parkinson-White syndrome who underwent successful radiofrequency catheter ablation of their left-sided bypass tracts are described. Transesophageal echocardiography, a relatively new echocardiographic technique, was utilized in both patients and provided excellent visualization of intracardiac anatomy as well as the catheter tip. Transesophageal echocardiography was also synergistic with fluoroscopy and the intracardiac electrogram in providing more precise catheter placement. In addition, the use of transesophageal echocardiography may reduce fluoroscopic exposure and shorten the procedure time.

The echo Doppler spectrum of valvular abnormalities in the hospitalized octogenarian

Cardiac valves thicken and become more opaque with advancing age. As more individuals live longer and as more treatment modalities such as valvuloplasty evolve, the presence and significance of these valvular abnormalities become important. We retrospectively studied 628 octogenarian patients to try and define further the presence and significance of these abnormalities detected by Doppler echocardiography. A group of 547 patients were suitable for analysis. Age ranged from 80 to 96 years (mean 84.4). The female:male ratio was 1.9:1. Mitral, aortic, and tricuspid regurgitation (MR, AR, and TR) were significant if the jet moved greater than 2 cm from the plane of the valve away or toward the transducer, depending on transducer position. Mitral regurgitation was detected in 331 patients (60.5%) and was significant in 82 patients (15%). Aortic regurgitation was detected in 276 patients (50.5%) and was significant in 70 patients (12.8%). Tricuspid regurgitation was detected in 131 patients (23.9%) and was significant in 30 patients (5.5%). Regurgitant lesions were detected in two valves in 150 patients (27.4%) three valves in 57 patients (10.4%), in all four valves in 17 patients (3.1%). Aortic stenosis was detected in 160 patients (29.3%). The gradient range was 16-156 mmHg (mean 47.8). Significant aortic stenosis was present in 70 patients (12.8%) (gradient greater than 50 mmHg), of whom 54 had isolated pure aortic stenosis and 16 had mixed lesion. In 40% of these patients, significant aortic stenosis was an unexpected finding at two-dimensional echocardiography. Valvular pathology is common in the octogenarian population.(ABSTRACT TRUNCATED AT 250 WORDS)

High risk percutaneous transluminal coronary angioplasty in the treatment of severe coronary artery disease

We report on 27 "high risk" patients out of 171 consecutive patients undergoing percutaneous transluminal coronary angioplasty from June 1984 to August 1985. The ages ranged from 31-80 years (mean 62.7 +/- 10) years. High risk percutaneous transluminal coronary angioplasty was defined as: salvage cases (3 patients) where the patients presented in cardiogenic shock or the vessels were not bypassable; multivessel coronary artery disease (22 patients) where a large area of jeopardized myocardium was dependent on the angioplasty vessel(s); left ventricular dysfunction (7 patients) as defined by two of the three criteria: left ventricular end-diastolic volume index greater than 100 ml/m2; ejection fraction less than 30%; and left ventricular end-diastolic pressure greater than 20 mm Hg. The initial success rate in the high risk patients was 85.2%. Emergency coronary artery bypass surgery in these patients was 7.4%. There was one death in the high risk group, as one of the salvage cases died 24 hours after successful percutaneous transluminal coronary angioplasty due to severe underlying myocardial disease. In conclusion percutaneous transluminal coronary angioplasty can be successfully performed in high risk patients with a low complication rate and should be considered as an alternative to coronary artery bypass graft surgery in selected high risk patients.

Percutaneous transluminal coronary angioplasty of the "very proximal" coronary artery stenosis

We report on 11 patients with "very proximal" lesions out of a total of 300 consecutive patients who underwent percutaneous transluminal coronary angioplasty (PTCA). Eight patients had native left anterior descending (LAD) lesions and three had LAD saphenous vein grafts lesions. Lesions were considered to be "very proximal" when one half or more of the balloon was inflated in the left main coronary artery for the native LAD lesions or the aorta for the LAD coronary artery saphenous vein bypass graft (CABG) lesions. There was a mean reduction in stenosis from 88.3% (range 75-99) to 13.8% (range 0-60) and a mean reduction in transtenotic gradient from 47.2 mmHg (range 20-80) to 8.3 mmHg (range 0-20). The initial success rate was 90.9% (10 out of 11 patients) with a partial success in the other patient. No complications occurred in any of the patients. Two patients had restenosis (18.2%) at 3 months and 6 months, respectively, post-PTCA. It is concluded that "very proximal" lesions can be successfully dilated with a high initial success rate and low complication rate. Nevertheless, these lesions may present problems with guiding catheter stability and, because of the potential risk of circumflex (CX) occlusion, this vessel may have to be protected with a second guidewire.

Echocardiographic analysis of left ventricular filling in isolated pure chronic aortic regurgitation

Left ventricular (LV) diastolic filling was assessed using digitized M-mode echocardiography in 12 patients with aortic regurgitation (AR) and in 12 normal subjects. Ten patients with AR were asymptomatic and 2 patients had congestive heart failure. LV chamber dimensions, fractional shortening and the rate of change of LV dimensions during systole and diastole were determined. In addition, the timing of the rate of change of LV dimensions in diastole (peak dD/dt, 50% peak dD/dt and 20% peak dD/dt) was also measured. Patients with AR had a significant reduction in dD/dt (12.2 +/- 3.5 cm/s in patients with AR vs 15.9 +/- 1.9 cm/s in normal subjects, p less than 0.01) and a delay in the timing of peak dD/dt (160 +/- 35.2 ms in patients with AR vs 86 +/- 17.6 ms in normal subjects, p less than 0.01) from the minimum LV dimension. These diastolic abnormalities were present in patients with symptomatic as well as those with asymptomatic AR, occurred even when the fractional shortening and peak systolic emptying rate (peak -dD/dt) were normal, and showed no correlation with the calculated LV mass (r = 0.14). The delay in the diastolic filling velocities (peak dD/dt, 50% and 20% peak dD/dt) was associated with a decreased rate of change of LV dimension in diastole, suggesting delayed early LV filling. These findings indicate an abnormality of LV diastolic filling in patients with symptomatic as well as asymptomatic AR and suggest that diastolic abnormalities may precede echocardiographic indexes of systolic LV dysfunction.

Geriatric cardiology: managing the most common nonischemic disorders

Two-dimensional echocardiography is the method of choice for calculation of left ventricular mass, especially in patients with abnormal left ventricular geometry and segmental disease. Predominating diastolic abnormalities may be responsible for signs and symptoms of heart failure in some patients. These patients should not be treated in the conventional manner, but require special treatment with beta blockers or calcium-channel blocking agents.

Magnetic resonance imaging and two-dimensional echocardiography. Alternative approach to aortography in diagnosis of aortic dissecting aneurysm

Unrecognized acute dissection of the aorta requires rapid and accurate diagnosis for appropriate management. The "gold standard" for diagnosis has been invasive angiography, but this diagnosis can be achieved noninvasively via two-dimensional echocardiography, computed tomographic scanning, and magnetic resonance imaging. Two patients are described in whom echocardiography and magnetic resonance imaging were complementary diagnostic aids. The advantages and disadvantages of echocardiography, computed tomographic scanning, magnetic resonance imaging, and aortography in aortic dissection are discussed. It is anticipated that a combination of noninvasive diagnostic aids will eliminate the need for invasive angiography in many instances in the future.

The complementary role of magnetic resonance imaging, Doppler echocardiography, and computed tomography in the diagnosis of dissecting thoracic aneurysms

Non-ECG gated MRI was compared with 2DE and/or CT scans in 10 patients with dissecting aneurysms proven by angiography and/or surgery. Patient ages ranged from 48 to 85 years (mean 69.6). Six had DeBakey type I dissections and four had DeBakey type III dissections. MRI was diagnostic for aortic dissection in nine cases and suggestive in the tenth. 2DE was diagnostic in six out of nine patients, suggestive in two patients, and nondiagnostic in one patient. CT was diagnostic in the three cases in which it was employed. MRI demonstrated a dilated ascending aorta with thickened walls in all type I dissections as well as an intimal flap and slow flow in the false channel in four patients. In the other two patients with type I dissection, MRI detected the intimal flap in the descending aorta but not in the ascending aorta, whereas 2DE revealed the ascending aortic intimal flap in both of these patients and CT showed it in one of them. In the type III dissections, MRI demonstrated a thickened wall and thrombus in the lumen in all four cases, and the intimal flap in three out of the four. 2DE excluded ascending aortic involvement in all three type III dissections. Six other patients with fusiform dilated ascending aortas had no evidence of dissection by MRI, 2DE, and aortography. Thus, non-ECG gated MRI alone or in combination with 2DE and/or CT is useful in the diagnosis of dissecting thoracic aneurysm and in assessing the extent of the dissection. In addition, the differentiation of dissecting aneurysms of the aorta from fusiform dilatation of the aorta is made possible by these noninvasive techniques.

Contribution of echocardiography and immediate surgery to the management of severe aortic regurgitation from active infective endocarditis

The timing of surgery in patients with severe aortic regurgitation and left ventricular (LV) failure, particularly when associated with active infective endocarditis (IE), is of the utmost importance. From July 1982 to May 1984, 34 patients, aged 15 to 60 years, with severe aortic regurgitation underwent immediate (within 24 hours of diagnosis) aortic valve surgery. All patients were in New York Heart Association class IV for LV failure. Eighteen patients had right-sided heart failure. Decision for immediate surgery was based on the echocardiographic demonstration of diastolic closure of the mitral valve or of vegetations on the aortic valve. Premature closure of the mitral valve was demonstrated echocardiographically in 17 patients, 13 of whom had diastolic crossover of LV and left atrial pressure tracings recorded at surgery. IE of the aortic valve was confirmed at surgery in 29 patients, 27 of whom had vegetations on echocardiography. Seven patients required replacement of both aortic and mitral valves. Antibiotic therapy for IE was started immediately after blood cultures were taken and continued for 4 to 6 weeks postoperatively. The mortality rate within 30 days of surgery was 6% for the group as a whole and 7% for those with IE. Mean follow-up period for the 32 survivors was 10.6 months. There were 2 late deaths. No patient had periprosthetic regurgitation or persistence of endocarditis. Procrastination in referral for surgery of these extremely ill patients is not justified and is likely to be associated with higher risks of morbidity and mortality.

The uses of two-dimensional Doppler echocardiographic techniques preoperatively and postoperatively in a ventricular septal defect caused by penetrating trauma

Doppler echocardiography was used to determine the site and size of a ventricular septal defect in a patient with a penetrating wound of the heart. Additional physiological measurements by Doppler study, including pulmonary artery pressure and degree of left-to-right shunting, were helpful in deciding on surgical closure of the defect as the definitive therapy in this patient. Associated intracardiac defects (e.g., mitral or tricuspid regurgitation) can be excluded by Doppler echocardiography.

Persistent ST-segment elevation in patients with anterior myocardial infarctions. Evaluation by exercise electrocardiography, echocardiography and Holter monitoring

One hundred and seventy patients who suffered an acute myocardial infarction (MI) were followed up at 3-monthly intervals by a full clinical evaluation, exercise electrocardiography and ambulatory Holter monitoring. Fifty-eight patients (34%) had anterior MIs, and of these 23 (40%) had persistent ST-segment elevation over the infarct zone, reflected by leads presenting with Q-S configuration. Fifteen (65,2%) of the latter demonstrated further ST-segment elevation during exercise. They were further investigated by cross-sectional echocardiography. Left ventricular (LV) dysfunction was diagnosed in 87% of patients with persistent ST-segment elevation, and in 93% of the patients with additional exercise-induced ST-segment elevation. Organized thrombi occurred in 2 patients (8,7%) and 1 experienced a transient ischaemic attack. Ventricular arrhythmias occurred frequently (ventricular ectopy--91,3%, ventricular tachycardia--17,4%, and couplets--47,8%). Death occurred in 3 patients (13,1%) and 1 patient (4,3%) had a second MI over a mean follow-up period of 83,6 months. This study suggests that persistent ST-segment elevation on the resting ECG of patients with anterior MIs is a reliable indicator of LV wall motion abnormalities, and that this correlation further increases if it is associated with exercise-induced ST-segment elevation. Furthermore, the role of echocardiography as a diagnostic tool in evaluating LV function is stressed. The prognosis of patients with post-infarction LV dysfunction is notably poor and may be the result of frequent complex ventricular arrhythmias.

Further experience with long-term captopril therapy in severe refractory congestive heart failure

Fifty patients in severe congestive heart failure (CHF) were treated with captopril (Capoten; Squibb), an oral angiotensin-converting enzyme inhibitor, over a 2-year period (range 3-24 months, mean 8,6 +/- 7,7 months). At entry, all patients were in New York Heart Association (NYHA) functional class IV despite high-dose diuretic and conventional vasodilator therapy. The overall cumulative survival at 6 and 12 months was 64% and 53% respectively. There were 22 deaths (18 during captopril therapy) including 8 sudden deaths. At 2-year follow-up (mean 14,6 +/- 6,9 months), there were 25 survivors on captopril; 18 in NYHA class I or IIS and 7 in class IIM or III. Diuretic requirements were decreased considerably in all. Side-effects were common but transient and in no case did captopril have to be withdrawn. We confirm our earlier conclusion that captopril has long-term beneficial effects and is a highly effective drug in the treatment of patients with CHF refractory to currently accepted therapy. Sudden death despite satisfactory clinical improvement continues to cause concern. Precautions which may reduce or avoid these are briefly discussed.

The dilemma of the creatine kinase cardiospecific iso-enzyme (CK-MB) in marathon runners

Serum creatine kinase iso-enzyme (CK-MB) levels were measured in 51 marathon runners before and after a 50 km marathon event. Ninety-five per cent of the runners were found to have pathologically elevated values, i.e. CK-MB concentrations were elevated to the range normally considered indicative of myocardial necrosis. Results indicate that a rise in the CK-MB level is common after marathon running. We therefore believe that cardiac enzymes are an unreliable indicator of myocardial infarction in patients who experience chest pain following strenuous muscular exercise.

Postexercise blood pressure as a predictor of hypertension

A study on 721 healthy male aircrew assessed whether the blood pressure response to exercise could be used to predict the development of hypertension. A positive blood pressure response to exercise, recorded 30 s after the completion of exercise, was defined as a systolic blood pressure of 200 torr or more (systolic test) or a raised diastolic blood pressure (diastolic test). While 236 (32.7%) became hypertensive with a blood pressure greater than 149/90 torr, 17% of these had shown a positive systolic response and 17% a positive diastolic response. The other 485 individuals (67.3%) remained normotensive throughout the mean follow-up period of 68 months (range 12-170 months). Of this group, 88% never manifested a positive systolic or diastolic response to exercise. Although 5% of the normotensive subjects manifested a positive systolic response to exercise, and 12% manifested a positive diastolic response to exercise, a longer period of follow-up may reduce this figure. It is concluded that exercise related blood pressure is a useful test in predicting the development of essential hypertension.

The natural history of the Q wave in inferoposterior myocardial infarction

One hundred and twenty-five patients who had suffered transmural inferior myocardial infarctions were followed up for a mean period of 55 months. On electrocardiography the area under the pathological Q waves in the inferior leads was measured serially. Eighty-one patients (65%) showed a highly significant time-related diminution in Q-wave area. The ECGs of 17 subjects (14%) became normal and there was no electrocardiographic evidence of the previous myocardial infarction. The Q waves of the remaining 44 subjects (35%) remained constant or increased. A discussion of the possible mechanisms of changes in Q-wave size follows.

Correlation of ventricular ectopic activity and exercise-related ST-segment changes

Same-day exercise electrocardiography and ambulatory electrocardiographic (Holter) monitoring were performed on 167 patients, all of whom had suffered myocardial infarctions over the past 12 years. A significant correlation (P less than 0,0001) was found when comparing exercise testing for ischaemic ST-segment changes and the number of complexity of ventricular arrhythmias found on Holter monitoring. Two different methods of arrhythmia classification were used and the results were similar. The value of simultaneous Holter monitoring and exercise electrocardiography to detect 'late' exercise-related ventricular arrhythmias was not found to be sufficient to warrant their widespread simultaneous use.

Lack of correlation between the clinical assessment of cardiovascular status and exercise electrocardiography

One hundred and seventy-one patients who had had a myocardial infarction were evaluated at the Institute for Aviation Medicine, Pretoria. Patients were graded according to the New York City Heart Association classification of cardiac functional capacity and then subjected to exercise electrocardiography. Only 20% of the 74 patients whose exercise electrocardiograms revealed ischaemic heart disease felt that their cardiovascular function was limiting their daily activity. This lack of correlation between the two forms of assessment was highly significant (P less than 0,0001). It is therefore concluded that clinical evaluation of an individual with known ischaemic heart disease may be misleading.

Familial thrombosis associated with antithrombin III deficiency in a young adult male. A case report

Congenital antithrombin III deficiency is a rare but well-documented abnormality. A young man presented with pulmonary embolism and was found to be suffering from this condition. His family history revealed numerous members with venous disease and its complications. Treatment of the acute episode and prophylaxis are discussed.