Residual risk after acute coronary syndrome: the PRATO-ACS Registry

Background

Despite administration of current evidence-based therapies, substantial residual risk for cardiovascular events persists, particularly after acute coronary syndrome (ACS). It is well known that different inflammatory, metabolic, renal factors concur in defining the residual risk, beyond lipids, platelets and coagulation.

Purpose

The purpose of this study is to analyze the prevalence of various residual risk factors in patients at 1 month after ACS and their association with all-cause death within 3 years.

Methods

Of the 1585 patients admitted to our center for ACS and included in the PRATO-ACS Registry we selected the 1099 patients (69±12 yrs; 30% female; 26.7% with diabetes; 73% NSTE-ACS and 27% STEMI) who underwent laboratory analyses 1 month after the index event. All patients had undergone early invasive strategy and received high intensity statins during hospitalization and at discharge. The frequency of 5 specific risk factors was evaluated: LDL cholesterol ≥70 mg/dl; high sensitivity C reactive protein (hs-CRP) ≥2 mg/l; triglycerides ≥135 mg/dl; high glycosylated hemoglobin (HbA1c) ≥6.5% in diabetic and ≥5.7% in non-diabetic patients; decrease in estimated glomerular filtration rate (eGFR) ≥25% compared to baseline. Patients were followed up for three years. The association between the individual risk factors and all-cause death within 3 years was evaluated with Cox proportional analysis expressed by hazard ratio (HR) and 95% confidence intervals (CI).

Results

The Table lists the prevalence of the five residual risk factors at 1 month and the mortality HR (95% CI) within 3 years for each risk factor.

Conclusions

After ACS, despite the secondary prevention therapy (high intensity statins), residual risk factors, all measured at 1 month, are persistently elevated in the majority of patients. Their association with all-cause death at 3 years is significantly high for inflammatory and metabolic parameters as well as renal function deterioration. These findings should prod us to develop new strategies that target all residual risk factors, not only lipid profile.

Funding Acknowledgement

Type of funding sources: None.

The unfinished work of neonatal very low birthweight infants quality improvement: Improving outcomes at a continental level in South America

Neonatal mortality rate varies between 4.2 and 18.6 per thousand by country in South America. There is little information regarding the outcomes of very low birth weight infants in the region and mortality rates are extremely variable ranging from 6% to over 50%. This group may represent up to 50-70% of the neonatal mortality and approximately 25-30% of infant mortality. Some initiatives, like the NEOCOSUR Network, have systematically collected and analyzed epidemiological information on VLBW infants' outcomes in the region. Over a 16-year period, survival without major morbidity improved from 37 to 44%. However, mortality has remained almost unchanged at approximately 27%, despite an increase in the implementation of the best available evidence in perinatal practices over time. Implementing quality improvement initiatives in the continent is particularly challenging but represents a great opportunity considering that there is a wide margin for progress in both care and outcomes.

Prediction of high on-treatment platelet reactivity in clopidogrel-treated patients with acute coronary syndromes

BACKGROUND

About 40% of clopidogrel-treated patients display high platelet reactivity (HPR). Alternative treatments of HPR patients, identified by platelet function tests, failed to improve their clinical outcomes in large randomized clinical trials. A more appealing alternative would be to identify HPR patients a priori, based on the presence/absence of demographic, clinical and genetic factors that affect PR. Due to the complexity and multiplicity of these factors, traditional statistical methods (TSMs) fail to identify a priori HPR patients accurately. The objective was to test whether Artificial Neural Networks (ANNs) or other Machine Learning Systems (MLSs), which use algorithms to extract model-like 'structure' information from a given set of data, accurately predict platelet reactivity (PR) in clopidogrel-treated patients.

METHODS

A complete set of fifty-nine demographic, clinical, genetic data was available of 603 patients with acute coronary syndromes enrolled in the prospective GEPRESS study, which showed that HPR after 1month of clopidogrel treatment independently predicted adverse cardiovascular events in patients with Syntax Score >14. Data were analysed by MLSs and TSMs. ANNs identified more variables associated PR at 1month, compared to TSMs.

RESULTS

ANNs overall accuracy in predicting PR, although superior to other MLSs was 63% (95% CI 59-66). PR phenotype changed in both directions in 35% of patients across the 3 time points tested (before PCI, at hospital discharge and at 1month).

CONCLUSIONS

Despite their ability to analyse very complex non-linear phenomena, ANNs or MLS were unable to predict PR accurately, likely because PR is a highly unstable phenotype.

Efficacy and safety of withholding antimicrobial treatment in children with cancer, fever and neutropenia, with a demonstrated viral respiratory infection: a randomized clinical trial

OBJECTIVES

To determine efficacy and safety of withholding antimicrobials in children with cancer, fever and neutropenia (FN) with a demonstrated respiratory viral infection.

METHODS

Prospective, multicentre, randomized study in children presenting with FN at five hospitals in Santiago, Chile, evaluated at admission for diagnosis of bacterial and viral pathogens including PCR-microarray for 17 respiratory viruses. Children positive for a respiratory virus, negative for a bacterial pathogen and with a favourable evolution after 48 h of antimicrobial therapy were randomized to either maintain or withhold antimicrobials. Primary endpoint was percentage of episodes with uneventful resolution. Secondary endpoints were days of fever/hospitalization, bacterial infection, sepsis, admission to paediatric intensive care unit (PICU) and death.

RESULTS

A total of 319 of 951 children with FN episodes recruited between July 2012 and December 2015 had a respiratory virus as a unique identified microorganism, of which 176 were randomized, 92 to maintain antimicrobials and 84 to withdraw. Median duration of antimicrobial use was 7 days (range 7-9 days) versus 3 days (range 3-4 days), with similar frequency of uneventful resolution (89/92 (97%) and 80/84 (95%), respectively, not significant; OR 1.48; 95% CI 0.32-6.83, p 0.61), and similar number of days of fever (2 versus 1), days of hospitalization (6 versus 6) and bacterial infections throughout the episode (2%-1%), with one case of sepsis requiring admission to PICU in the group that maintained antimicrobials, without any deaths.

CONCLUSIONS

The reduction of antimicrobials in children with FN and respiratory viral infections, based on clinical and microbiological/molecular diagnostic criteria, should favour the adoption of evidence-based management strategies in this population.

Lingual thyroid causing dysphagia and dyspnoea. Case reports and review of the literature

Lingual thyroid is a rare embryological anomaly and originates from failure of the thyroid gland to descend from the foramen caecum to its normal eutopic pre-laryngeal site. The ectopic gland located at the base of the tongue is often asymptomatic but may cause local symptoms such as dysphagia, dysphonia with stomatolalia, upper airway obstruction and haemorrhage, often with hypothyroidism. Two cases are presented, one in a 62-year-old female and the other in a 42-year-old female, both of whom complained of sensation of a foreign body and progressive dysphagia and dyspnoea caused by ectopic lingual thyroid. Treatment was performed with a partial endoscopic removal and an external cervical approach, followed by substitutive hormone treatment, respectively. Diagnostic procedures and therapeutic options are discussed and a review has been made of reports of lingual thyroid appearing in the literature.

Mechanical Synchrony: Role of Surgical Ventricular Restoration in Correcting LV Dyssynchrony During Chamber Rebuilding

Cardiac failure is frequently complicated by intra and or interventricular conduction delay that results in dyssynchronized cardiac contraction and relaxation. In contrast to an electrical intervention by biventricular pacing, this study tests the capacity of geometric rebuilding by surgical ventricular restoration (SVR) to restore a more synchronous contractile pattern through mechanical reconstruction without exogenous pacing input. Thirty patients (58 +/- 8 years) undergoing SVR at the Cardiothoracic Center of Monaco were prospectively evaluated with a protocol which uses simultaneous measurements of ventricular volumes and pressure to construct pressure/volume (P/V) and pressure/length (P/L) loops. Mean QRS duration was within normal limits (100 +/- 17 ms) preoperatively. Preoperative LV contraction was highly asynchronous. Endocardial time motion was either early or delayed at the end-systolic phase, yielding P/L loops with abnormal in size, shape, and orientation. Postoperatively, SVR resulted in leftward shifting of P/V loops and increased area; endocardial time motion and P/L loops almost normalized. The hemodynamic consequences of SVR included improved ejection fraction; reduced end-diastolic and end-systolic volume index; more rapid peak filling rate; peak ejection rate and mechanical efficiency resulting in mechanical intraventricular resynchronization that improves LV performance.

Intermediate survival and predictors of death after surgical ventricular restoration

This study examined the effects of Dor procedure on long-term survival in patients with previous transmural anterior myocardial infarction who were referred to a single experienced center for left ventricular reconstruction by endoventricular patch-plasty repair. Our aim was to evaluate the impact of this procedure on long-term survival and to assess the ability of preoperative, perioperative, and postoperative variables to predict late survival. Major indications for surgery were left ventricular dysfunction, angina, ventricular arrhythmias, or a combination of the three; 20 patients underwent urgent cardiac surgery. The total group was 245 patients, with 8.1% hospital mortality, and 19 patients lost to follow-up [corrected]. The study group comprised 207 patients. Many pre- and postoperative clinical, hemodynamic, and functional variables, as well as operative parameters, were studied by univariate analysis. During a mean follow-up period of 39+/-19 months, 30 end points were observed, including 27 deaths and 3 heart transplants. Event-free survival was 98%+/-1% at 1 year, 95.8%+/-1.4% at 2 years, and 82.1%+/-3.3% at 5 years. Cox regression analysis showed preoperative New York Heart Association functional class, ejection fraction, end systolic volume index, and remote asynergy as independent predictors of mortality. The procedure has a favorable impact on 5-year survival. Independent predictors of late survival are the preoperative functional status and the left ventricular systolic function.

Effects of the Dor procedure on left ventricular dimension and shape and geometric correlates of mitral regurgitation one year after surgery

OBJECTIVES

In the present study we retrospectively analyzed ventriculographic data from symptomatic patients after myocardial infarction who underwent the Dor procedure (endoventricular circular patch plasty repair) to evaluate left ventricular shape 1 year after the operation and to analyze the geometric correlates of late mitral regurgitation.

METHODS

Forty-four patients with previous transmural anterior myocardial infarction comprised the study group. Left ventricular volumes, global left ventricular systolic and diastolic sphericity, the extent of wall motion abnormalities, and the presence and degree of mitral regurgitation were analyzed before and 1 year after operation.

RESULTS

Comparing preoperative diastole to systole within the cardiac cycle, left ventricular shape becomes more elliptical in systole than it was in diastole (eccentricity index closer to 1). The intervention leads to an increased diastolic sphericity, but for each cardiac cycle, the systolic shape is more elliptical relative to its diastolic counterpart in respect to basal conditions. Mitral regurgitation was detected after operations in 17 patients; 14 of them did not have mitral regurgitation before operations. Patients with late mitral regurgitation had greater preoperative volumes and more spherical chamber than did patients without late mitral regurgitation.

CONCLUSIONS

Despite a more spherical postoperative left ventricular chamber, systolic pump function improves after the Dor procedure, mainly for the improvement in inferior wall shortening. The presence of late mitral regurgitation is relatively frequent in this series of patients, and this emphasizes the importance of a more accurate quantitative evaluation of preoperative functional mitral regurgitation to repair the valve when appropriate. Geometric correlates of late mitral regurgitation appeared to be greater chamber sphericity and larger ventricular volumes preoperatively.

Effects of reconstructive surgery for left ventricular anterior aneurysm on ventriculoarterial coupling

OBJECTIVE

To investigate left ventricular elastance (Emax) and effective arterial elastance (Ea) in postinfarction left ventricular aneurysm and evaluate their role in left ventricular function improvement after endoventricular circular patch plasty (EVCPP). Ventriculoarterial coupling has never been studied in these patients.

PATIENTS

22 consecutive patients (49 to 73 years) with left ventricular anterior aneurysm.

METHODS

Haemodynamic studies were done before and two weeks after EVCPP. Ventriculography was performed during atrial pacing (100 beats/min). Pressure/volume loops were analysed and derived parameters measured. Emax was estimated by applying the "single beat" method. Ea was calculated as end systolic pressure/stroke volume.

RESULTS

Left ventricular volumes and Ea decreased after surgery: end diastolic volume index from mean (SD) 155 (53) to 106 (29); end systolic volume index from 112 (51) to 62 (30) ml/m2 (both p < 0.0001); Ea from 1.65 (0.70) to 1.39 (0.41) mm Hg/ml (p = 0.04). Ejection fraction and Emax increased, without significant changes in stroke volume and work. The decrease in Ea was directly correlated with its preoperative value. The time interval between left ventricular pressure upstroke and peak systolic pressure decreased, from 237 (39) to 191 (41) ms (p < 0.0001), paralleling morphological changes in pressure tracings.

CONCLUSIONS

After EVCPP, ventriculoarterial coupling improves because of the fall in Ea caused by end systolic pressure reduction. The improvement is related to aortic pressure waveform changes and improved relaxation.

Regional and temporal nonuniformity of shape and wall movement in the normal left ventricle

Asymmetry of left ventricular (LV) shape and asynchrony of regional LV movement have been described in the normal human heart, but never correlated to each other. In 16 normal subjects, right anterior oblique ventriculography was used to obtain volumes, regional wall motion (centerline method) and curvature (windowed Fourier series approximation of contours) over the entire cardiac cycle. The apex had the greatest curvature, while the posterior wall had a negative end-diastolic curvature that decreased further at early-systole and became positive at end-systole. The anterior region had the greatest and the anteroapical region the least fractional shortening. Asynchrony was evident as a delayed contraction of the infero- and anteroapical regions, and as a greater rate of late-systolic shortening of the anterior wall than that of the apex. Shape changes and shortening were dyssynchronous in the apical regions where the greatest changes occurred at early diastole. Temporal and regional nonuniformity of shape and movement exists in normal subjects. Dyssynchrony between shape and regional contraction of the apical regions deserves further studies.

Efficacy of endoventricular patch plasty in large postinfarction akinetic scar and severe left ventricular dysfunction: comparison with a series of large dyskinetic scars

BACKGROUND

Many believe that dyskinesia is the only predictor of favorable surgical outcome after large myocardial infarction and that akinetic scars do not recover well in patients with globally depressed ventricular function.

METHODS

This study evaluates clinical and hemodynamic results of endoventricular circular patch plasty in patients with either large akinetic scar (n = 51) or large dyskinetic scar (n = 49) and depressed left ventricular function (ejection fraction <30%). Groups were comparable for symptoms, indication for operation, and delay from myocardial infarction. Heart failure was a major indication for operation in both groups. Coronary grafting was performed in 98% of patients: 10 had mitral valve repair or replacement, and 47 patients with preoperative ventricular arrhythmias had cryotherapy. In-hospital mortality was 12% (five patients in the akinetic group [10%] and seven in the dyskinetic group [14%]).

RESULTS

Results showed an early and late improvement in New York Heart Association functional class and ejection fraction (from 23% +/- 5% to 31% +/- 11% to 40% +/- 13% in akinetic patients and from 23% +/- 6% to 41% +/- 10% to 41% +/- 12% in dyskinetic patients). Ventricular tachycardia was reduced significantly in both groups early and late after the operation.

CONCLUSION

We conclude that in patients with either large akinetic or dyskinetic scar and severe left ventricular dysfunction, endoventricular circular patch plasty associated with coronary grafting and cryotherapy, when indicated, provides surviving patients with significant improvement in cardiac function. This approach can be considered as an alternative to heart transplantation in patients with severe left ventricular dysfunction.

Akinetic versus dyskinetic postinfarction scar: relation to surgical outcome in patients undergoing endoventricular circular patch plasty repair

OBJECTIVES

This retrospective study attempted to relate surgical outcome with the extent and type of preoperative wall motion asynergy in patients with postinfarction myocardial scar who underwent endoventricular circular patch plasty repair and associated coronary grafting.

BACKGROUND

Left ventricular (LV) pump function improvement is difficult to predict after aneurysmectomy, for either akinetic or dyskinetic scar, and previous studies have reported that the absence of paradoxic systolic motion correlates with higher operative mortality and no improvement in pump function.

METHODS

Two hundred forty-five patients who underwent endoventricular circular patch plasty repair and associated coronary grafting were retrospectively selected if they had technically adequate right and left anterior LV angiograms before the operation. All had right and left cardiac catheterization. The centerline method was applied to preoperative right anterior oblique LV angiography to assess the absolute motion of the chords and the percent length of the perimeter showing a fractional shortening <2 SD from the normal mean value (extent of asynergy ([A%]).

RESULTS

The overall perioperative mortality rate was 6%; 120 patients had akinetic and 125 had dyskinetic scar, and no differences were found among the groups in terms of all the clinical and hemodynamic variables collected in the study. Patients with a large scar (A% >60), either akinetic or dyskinetic, had a higher perioperative mortality rate (12%) than patients with a small scar (2.2%). After the operation, the ejection fraction (EF) increased from 36 +/- 13% to 50 +/- 13% (mean +/- SD), and pulmonary pressures significantly decreased. End-diastolic volume decreased from 199 +/- 75 to 89 +/- 36 ml/m2. Patients with a large akinetic scar had the most severely impaired preoperative function (largest ventricular volumes and highest pulmonary mean pressure); nevertheless, they had an impressive improvement in function (EF from 25 +/- 9% to 41 +/- 12%), not different from that observed with large dyskinetic scarring (EF from 26 +/- 7% to 46 +/- 11%).

CONCLUSIONS

Surgical outcome of endoventricular circular patch plasty repair for postinfarction myocardial scar relates to the extent of LV asynergy rather than to the presence or absence of dyskinesia. Patients with a large akinetic scar and severely depressed pump function benefit from a relatively simple surgical procedure previously reserved only for dyskinetic aneurysm. The reduction of wall tension and oxygen demand, owing to the marked decrease of volumes, and the increase in oxygen supply, owing to revascularization, may play a major role in improving pump function.

Late hemodynamic results after left ventricular patch repair associated with coronary grafting in patients with postinfarction akinetic or dyskinetic aneurysm of the left ventricle

This study reports hemodynamic, electrophysiologic, and clinical results in 171 patients (157 men and 14 women, mean age 57 +/- 8 years) 1 year after endoventricular circular patch repair and coronary grafting for postinfarction left ventricular dyskinetic or akinetic aneurysm. All patients had hemodynamic and electrophysiologic study before the operation and early and 1 year after the operation. The vast majority of aneurysms were anterior (n = 166), with a mean delay from infarction of 43 +/- 50 months. Fifty-two percent of patients were in New York Heart Association class III or IV, and preoperative ejection fraction was less than 40% in the majority of them (75%). Preoperative clinical ventricular tachycardia was present in 25 patients and was inducible in 59 patients. All patients had endoventricular circular patch repair with a synthetic (n = 99) or autologous patch (n = 72); 96% had associated coronary grafting with a mean number of bypass grafts of 1.9 +/- 0.9. Results at 1 year demonstrated a significant increase in ejection fraction (from 36% +/- 13% to 46% +/- 12% (p < 0.0001) and a significant reduction in ventricular volumes (end-diastolic volume index from 116 +/- 5 to 94 +/- 29 ml/m2 and end-systolic volume index from 77 +/- 45 to 53 +/- 25 ml/m2, p < 0.0001). New York Heart Association functional classification was significantly improved (2.6 +/- 0.9 vs 1.4 +/- 0.6, p < 0.0001) and ventricular tachycardias were almost suppressed (no documented clinical ventricular tachycardias and 8% incidence of inducible ventricular tachycardias after 1 year, chi 2 < 0.001). Patients who benefit most from the operation are those with more severe preoperative left ventricular dysfunction (i.e., ejection fraction < 30%), more frequent ventricular arrhythmias, and larger ventricular volumes. At regression analysis, critical disease of the right coronary artery was the only independent predictor of unsatisfactory pump improvement (as evaluated by postoperative increase of ejection fraction < 10 absolute points). In conclusion, in our large series of patients operated on by one surgical team between 1988 and 1993, who were studied hemodynamically both before and after the operation, endoventricular circular patch repair of left ventricular aneurysm associated with coronary grafting definitely improves left ventricular pump function and clinical status 1 year after the operation.

Outcome of left ventricular aneurysmectomy with patch repair in patients with severely depressed pump function

To determine the efficacy of left ventricular (LV) aneurysm resection and endoventricular patch repair with septal exclusion in patients with severely depressed pump function, we retrospectively selected 62 patients (mean age 59 +/- 7 years) with preoperative LV ejection fraction < or = 20%, from a series of 322 patients with postinfarction LV aneurysm who underwent this type of surgery at our center during a 5-year period. Mean ejection fraction was 17 +/- 3%; all patients were in New York Heart Association (NYHA) class III/IV, and all had hemodynamic and electrophysiologic studies before and after surgery. We analyzed both operative and long-term survival, and hemodynamic, electrophysiologic, and angiographic variables, as well as the symptomatic state after surgery. Follow-up was available in all patients (mean 23 +/- 14 months). Subtotal endocardiectomy and cryotherapy were associated in patients presenting with spontaneous or inducible ventricular arrhythmias (VA). Hospital mortality rate was 19.3%. Ejection fraction improved from 17 +/- 3% to 37 +/- 10% (p < 0.001); ventricular arrhythmias decreased significantly after surgery. Factors influencing early mortality at multivariate analysis were the presence of critical lesions on the circumflex artery and the duration of cardiopulmonary bypass. At 1-year control, a significant reduction in NYHA class was observed and no patient was in NYHA class IV. The improvement in ejection fraction was maintained (39 +/- 11%), as well as the reduction in inducible and spontaneous ventricular arrhythmias. There were 5 late deaths at follow-up, accounting for a late mortality of 10% at 5 years.

Regional myocardial performance of non-ischaemic zones remote from anterior wall left ventricular aneurysm. Effects of aneurysmectomy

The aim of this work was to investigate the effects of resecting a post-infarction left ventricular anterior aneurysm on the kinetics of the non-ischaemic inferior wall, remote from the healed lesion. Thirteen patients, with an anterior post-infarction aneurysm and a normal right coronary artery who underwent aneurysmectomy with endoventricular circular patch plasty reconstruction, had a complete haemodynamic study before and shortly after surgery. The shape of the left ventricle was quantitatively analysed by calculating the regional curvature at 90 points of the angiographic outlines (30 degrees right anterior oblique projection). Segmental wall motion was studied by means of the centreline method and by constructing pressure-length loops from the endocardial movement of 18 chords intersecting the left ventricular inferior contour and by simultaneously tracing the high-fidelity left ventricular pressure. Analysis of pressure-length regional loops showed a complex pattern of abnormal contraction and relaxation in the non-ischaemic inferior regions at baseline; after surgery such abnormalities decreased significantly and tended to revert to normal in many cases. Left ventricular shape in the inferior region was abnormal in 10/13 patients in that there was negative curvature at the interface between the aneurysm and the inferior wall that was corrected to positive after surgery. Regional inferior wall motion and global ejection fraction significantly improved after surgery in these 10 patients. The three patients whose global ejection fraction did not improve showed no inferior negative curvature pre-operatively, nor did they show an increase in inferior wall motion. The results indicate that regional function and shape in inferior, non-ischaemic regions, remote from an anterior aneurysm, are abnormal but potentially correctible if the abnormal mechanical burden imposed on the wall is relieved.

Sodium nitroprusside induces internalization of muscarinic receptors stably expressed in Chinese hamster ovary cell lines

We have characterized the internalization of muscarinic acetylcholine receptors induced by the nitric oxide (NO)-generating compound sodium nitroprusside. When Chinese hamster ovary cells, stably transfected with the human m4 muscarinic receptor subtype, were incubated for 1 h in the presence of 700 microM sodium nitroprusside, the number of receptors measured in intact cells with the hydrophilic ligand N-[3H]methylscopolamine was reduced by 30%. The effect was dose dependent, beginning with a concentration of sodium nitroprusside as low as 45 microM. Removal of sodium nitroprusside from the incubation medium did not result in a recovery of the binding sites. The phenomenon was temperature dependent and was blocked by the muscarinic antagonist atropine. No receptor diminution was detected when the number of binding sites was evaluated with the lipophilic antagonist [3H]quinuclidinyl benzilate. This indicates that sodium nitroprusside induces a redistribution of the muscarinic receptors between the plasma membrane and an internal compartment of the cell. Receptor loss was readily reversed by treatment with the sulfhydryl reducing agent diethyldithiocarbamate. Our data provide evidence that muscarinic receptors are internalized by sodium nitroprusside through the oxidation of sulfhydryl groups; they also suggest that NO could play a role in muscarinic receptor desensitization.

Alterations in left ventricular shape in patients with angina and single-vessel coronary disease

BACKGROUND

Left ventricular shape alterations, apparently independent of acute ischaemia or previous myocardial infarction, have been described in patients with stable angina. Our previous observations had been made in a group of patients with multivessel coronary disease; it was therefore not possible to establish a clear-cut anatomical relationship between the location of ischaemia and the changes in left ventricular contour. The aim of this work was to extend the previous observations by analysing left ventricular shape in patients with angina and single-vessel coronary disease, in whom the potentially ischaemic region can be easily localized.

METHODS

Fifty-eight patients with stable or unstable angina were retrospectively selected if they had single-vessel disease, normal regional and global function and no previous myocardial infarction: 37 had a critical stenosis (more than 75% diameter reduction) of the left anterior descending artery and 21 had a critical stenosis of the right coronary artery. Patients with left ventricular hypertrophy or any other obvious cause of myocardial dysfunction were excluded. All patients underwent haemodynamic study. Left ventricular global shape was evaluated by calculating eccentricity and circular indices; regional curvature was measured at 90 points along the angiographic contours (right anterior oblique projection) by applying a windowed Fourier analysis. Results were compared with those obtained in 16 normal subjects.

RESULTS

Patients had significant diastolic alterations in left ventricular shape, which assumed a more rounded aspect than normal. Regional curvature was significantly altered at several points pertaining to the anterior, apical and inferior segments. The pattern of changes in regional curvature was about the same in the left anterior descending and right coronary artery groups, with the involvement of regions supplied by angiographically normal arteries, although the extent of alteration was greater in patients with stable, chronic angina (more than 6 months) and in patients with stenosis of the left anterior descending artery.

CONCLUSIONS

Patients with angina, no previous myocardial infarction and normal systolic function had left ventricular shape abnormalities either in the potentially ischaemic or in the remote zones. The mechanism leading to these changes is still speculative.

Left ventricular shape changes induced by aneurysmectomy with endoventricular circular patch plasty reconstruction

Aneurysmectomy with left ventricular (LV) patch plasty reconstruction for anterior post-infarction LV aneurysm is usually followed by favourable haemodynamic results. The aim of this work was to describe the changes in LV shape induced by the intervention and to correlate them to the pre-operative data and to the surgical results. Twenty-two patients submitted to aneurysmectomy with this technique underwent a haemodynamic study before and 10-15 days after the intervention. Segmental wall motion was studied by the centreline method. LV shape was analysed by calculating the regional curvature of angiographic outlines (RAO 30 degrees projection). Results showed an improvement in LV pump function in 17 patients, which appeared mainly due to increased systolic shortening of the inferior wall. The intervention-induced modifications of LV geometry were characterized by: (1) marked reduction in end-diastolic volume, (2) shift of the angiographic apex counterclockwise, towards the aortic corner, (3) disappearance of the rim with negative curvature corresponding to the infero-apical border of the aneurysm, where the inferior wall resumed a normal outward convexity. No significant difference was found between the pre-operative haemodynamic data of patients who improved after surgery and those who did not. The presence of a rim of negative curvature at the infero-apical border of the aneurysm was the only pre-operative sign with a predictive value for the surgical outcome.

Results of nonguided subtotal endocardiectomy associated with left ventricular reconstruction in patients with ischemic ventricular arrhythmias

We analyzed the effects of nonguided endocardiectomy in patients with ischemic ventricular arrhythmias who underwent reconstructive operations for postinfarction left ventricular aneurysm. A total of 106 patients among 287 consecutive patients had spontaneous or inducible ventricular tachycardia (49 spontaneous and 57 inducible). Cryotherapy was done in 67 patients and coronary revascularization was done in 98%. Patients underwent complete hemodynamic study including programmed ventricular stimulation before and early after operation. Thirty-seven patients underwent hemodynamic evaluation after 1 year. The hospital mortality rate was 7.5%. At early and late studies the mean ejection fraction was significantly increased. Ventricular tachycardia was no longer inducible in 92% of patients after operation; only two patients had spontaneous ventricular tachycardia early after operation. At late study 10.8% of patients had inducible ventricular tachycardia and no spontaneous ventricular tachycardia was documented. All surviving patients had clinical follow-up (mean 21.3 months, range 2 to 64 months). There were eight late deaths and no episodes of ventricular tachycardia or syncope that necessitated hospitalization. In conclusion, nonguided, extended endocardiectomy associated with left ventricular reconstruction is safe and effective in curing ischemic spontaneous and inducible ventricular tachycardia.

[Diagnosis of neonatal femoral thrombosis following umbilical arterial catheterization by ultrasonic flow detection]

At her second day of life, a 2,200 g, 34 weeks gestational age female newborn infant with idiopathic respiratory distress syndrome, under treatment with mechanical ventilation and monitored through an umbilical arterial catheter (UAC), had severe clinical signs of arterial obstruction of her left limb. Signs of occlusion at the common femoral artery level were evident at Doppler ultrasonography. Doppler determinations showed early arterial blood flow improvement before amelioration of skin coloration and arterial pulses, that allowed close observation and withholding of surgical treatment which was finally not necessary. Eighteen newborn babies with an umbilical arterial catheter were then prospectively followed by Doppler ultrasound flow determinations. No further cases with clinical signs of arterial occlusion were found and Doppler studies performed in these late cases showed normal results in all of them. Doppler ultrasound flow determination is helpful for the diagnosis and management of lower limb arterial obstruction in newborn infants with umbilical arterial catheters.

[Mortality by birth weight and survival by gestational age and route of delivery in premature infants]

Specific mortality rates for birthweight (BW) and survival for gestational age were determined in babies under 1500 g and less than 34 weeks gestational age (GA), which were born in a private hospital at Santiago, Chile, between 1983 and 1988. Mortality rates were 875/1,000 in babies under 750 g, 391/1,000 for BW between 750 and 999 g, 185/1,000 for BW 1,000 to 1,249 g, and 125/1,000 in newborns who weighed 1,250 to 1,499 g. Survival increased with gestational age from 39% under 26 weeks to 57% at 26 and 27 weeks, reaching 83% at 28 and 29 weeks, 90% at 30 and 31 and 87% at 32 and 33 weeks. No significant difference was found neither in mortality nor in intracranial hemorrhage (ICH) incidence between newborns delivered by cesarean section or vaginal way. Survival of babies born after 26 weeks GA and weighing over 750 g was comparable with that reported by others. The type of delivery is not likely to play a role by itself in mortality or in incidence of severe ICH.