[Fast pathway for heart surgery]. / Vía rápida para cirugía cardiaca.

The increasing demographic and life expectancy rates, together with the vertiginous technological development during the last two decades, have raised the number of cardiac patients requiring surgical treatment. Therefore, several institutions have been forced to give priority to advanced or more serious cases and to postpone those that do not demand an urgent surgery. This analysis was made from June 15, 1999 to June 15, 2000 and demonstrates the results obtained from maintaining a fast track at the National Institute of Cardiology "Ignacio Chávez". This has favored the practice of surgeries in cases with noncomplex pathologies, null mortality, and low morbidity rates. The analysis also compares results from patients who had been subjected to surgery for the same type of pathologies but following the usual course of admittance and surgery scheduling, proving to be cost-efficient. It also demonstrates the high incidence of inter-auricular communication and the Von Willebrand disease that exist in our environment. Based on the results, we propose to maintain and increase this type of surgeries, addressing their limitations.

[Late thrombolysis and electrical stability in acute myocardial infarction. Role of the collateral flow]. / Trombolisis tardía y estabilidad eléctrica en el infarto agudo del miocardio: importancia del flujo colateral.

We evaluated 249 patients (pts) with first acute myocardial infarction: 1. Pts without thrombolysis, n = 119, 2. Pts treated with thrombolysis within 6 hours following MI, n = 80 and 3. Pts treated with thrombolysis between 6-12 hours after MI. Arrhythmic events were evaluated during follow up. All underwent heart rate variability studies and coronary angiogram where anterograde flow (TIMI) and collateral flow (Rentrop scale 0-2 = poor collateral flow and 3 = good collateral flow) were determined. Pts in group 2 and 3 showed a better anterograde and collateral flow than group 1 (p < 0.001). A lower spectral power in the high frequency band and a higher ratio low/high frequency band were observed in group 1 (p < 0.05). Conjunctive consolidation analysis showed more malignant arrhythmias in TIMI 0-2 with poor collateral flow than TIMI 0-2 with good collateral flow (17/138-12.3% vs 0/14-0%). Kaplan Meier analysis was able to demonstrate more cardiac sudden death events in TIMI 0-2 with poor collateral flow than TIMI 0-2 with good collateral flow or TIMI 3 (x2 = 7.22, p = 0.028), independently of thrombolytic treatment.

[Myocardial bridging. The role of microcirculation, coronary reserve and systolic endothelial injury]. / Puentes miocárdicos. Papel de la microcirculación, reserva coronaria y daño endotelial sistólico.

BACKGROUND: The relationship between myocardial bridging (MB) and ischemic heart disease is still controversial. However, a recent new evidence suggests that this relation is not by chance. PURPOSE: The purpose of our study was to review in a critical manner, the evidence for the relationship between MB and myocardial ischemia and its possible consequences. METHODS: We present 2 cases of our series and review the medical literature from January 1966 to January 1998 published and included in Medline and Current Contents. RESULTS AND CONCLUSIONS: The principal findings after this review were: 1) MB is not a normal variant; 2) The clinical impact of MB depends on its anatomical extension and degree of compressive effect; 3) The MB muscle is not similar to myocytes from other cardiac areas; 4) The environment surrounding coronary artery may be a crucial factor in determining whether the MB influences the induction of heart disorders or not; 5) The overshoot due to compressive effect on coronary artery might determine endothelial injury in the microcirculation post-MB; 6) In some cases, the systolic endothelial injury may contribute to release factors that are able to reduce the coronary reserve, resulting in myocardial ischemia; 7) The possible role of PTCA in this disorder still has to be proven. Surgical treatment should be considered when important myocardial ischemia had been demonstrated, even in those asymptomatic cases.

[High-fidelity spectrocardiography for the diagnosis of ischemic cardiopathy. The validation of a new method for analyzing the spectral components of the QRS complex]. / Espectrocardiografía de alta fidelidad para el diagnóstico de cardiopatía isquémica. Validación de un nuevo método para el análisis de los componentes espectrales del complejo QRS.

BACKGROUND: Analysis of high-frequency QRS complex envelope has been suggested as a method that could detect myocardial ischemia but the characteristics of the turbulence spectral from an spectral-temporal mapping into the QRS complex has not been studied yet. This is a prospective study of phase I for the validation of a new diagnostic test. AIMS: The aims for this study are: 1) To validate a new method for the detection of transient myocardial ischemia by both, high-frequency QRS and spectral turbulence analysis, which we have named "high-fidelity spectrocardiogram" (HFS). 2) To compare the sensitivity, specificity and accuracy of this HFS versus those obtained from nuclear medicine (NM-MIBI) and a conventional exercise ECG test, in a highly selected population. PATIENTS AND METHODS: Twenty-five patients (P) were studied: 10 P (Group B) with risk factors for coronary artery disease, without previous infarct, who had atypical precordial pain and a conventional ECG considered as "normal" by two cardiologists. The group A was formed by 15 P without risk factors or another kind of heart disease. All patients underwent a conventional surface ECG, which had to be normal in order to be considered for this study. Echocardiogram, exercise testing ECG and a NM-MIBI study were also normal. The HFS recording was taken before and after Dipyridamole testing, similar to the conventional method for the NM-MIBI (dipyridamole 0.25 mg/Kg/doses) studies. Our software for the analysis of QRS-frequencies was constructed from a language Turbo C++. The Fourier's transform allowed the construction of 3-dimensional graphics. After the determination of the best wide band for detecting changes in the frequency contained of QRS, the determination coefficients (r2) were obtained and compared before and after the challenge with dipyridamole. These changes were compared between groups (A vs B) later. RESULTS: The r2 changed more than 30% after dipyridamole in those patients in whom myocardial ischemia was demonstrated later by NM-MIBI. The sensitivity (85%) and specificity (90%) of HFS were similar to the nuclear medicine for identifying myocardial ischemia, but higher than a conventional exercise ECG testing (p.001). The main change in HFS was in the frequency-contained QRS in the 130-260 Hz band. The accuracy of our method was increased when an analysis of each orthogonal lead was made. There was a clear tendency of the group B to increase the QRS duration, while the contrary was found in group A, being the QRS the shorter (p.064). The chronological responses were different in those patients with ischemia. CONCLUSION: This study suggests that an episode of myocardial ischemia is able to change in a dramatic manner the frequency-contained within of the QRS complex, in spite of an unchanged ST segment in the conventional exercise ECG. We suggest that the HFS could be a good method for identifying myocardial ischemia. Its advantages could be important, particularly when the conventional exercise ECG is non informative.

[Percutaneous mitral valvuloplasty with the Inoue balloon. The initial experience and 3-year clinical follow-up at the Instituto Nacional de Cardiología Ignacio Chávez]. / Valvuloplastía mitral percutánea con balón de Inoue. Experiencia inicial y seguimiento clínico a 3 años en el Instituto Nacional de Cardiología "Ignacio Chávez".

In 113 patients with mitral stenosis a balloon mitral valvuloplasty (VMPB) was performed. There were 97 female and 16 male patients. Mean age was 40 +/- 11 with range of 18 and 70 years. 95 patients had sinus rhythm and 18 were on atrial fibrillation. Previous mitral commissurotomy was reported in 13 patients and 5 were pregnant at the moment of the procedure. Patients were carefully selected using both clinical and echocardiographic studies as well as the Wilkins score (SW). Transesophageal echocardiography (ETE) was performed when transthoracic echocardiography was not satisfactory. After right and left catheterization, VMPB was performed. In 106 patients (93.8%) a significant increase of the area mitral valve (AVM) was obtained. Echocardiographic results showed an AVM increase from 0.95 +/- 0.19 to 1.61 +/- 0.34 cm2 (p < 0.0001). Mean mitral gradient (GTM) decreased from 16.18 +/- 4.69 to 9.14 +/- 3.2 mmHg (p < 0.0001). Functional class improved in all patients in the long term. As complications there was severe mitral regurgitation (IM) reported in 6 patients who subsequently underwent mitral valve exchange, 2 of then died during surgery (one of them by bleeding and the other by non reparable rags on the atrium). A patient had cerebrovascular event (EVC) one week after the VMPB. In 3 of them non-significant interatrial communication (CIA) was produced. One patient died two months after the procedure due to bacterial endocarditis (EBSA). VMPB can be considered as a safe and effective treatment to patients with mitral stenosis.

[Electrocardiographic aspects of right ventricular repolarization in interauricular septal defect]. / Aspectos electrocardiográficos de la repolarización ventricular derecha en la comunicación interauricular.

In order to know the value of a peculiar right ventricular repolarization in the diagnosis of atrial septal defect. We studied-one hundred patients with main right bundle branch block and atrial septal defect confirmed by cardiac catheterization. The peculiar right ventricular repolarization consist in a straight and long S-T segment (longer than 160 msc) that form a 60 degrees or greater angle with the ascendent branch of the T wave. This electrocardiographic sign was found in 82 patients (sensitivity 82%). There were no differences between the age groups or the pulmonary pressure levels. In sixty five patients with main right bundle branch block without atrial septal defect, this peculiar right ventricular repolarization was investigated. It was found in fourteen cases (specificity 78.4%). Positive predictive value was 85.4%, negative predictive value 73.9% and diagnostic efficiency 80.6%. When the atrial septal defect was repaired (76 patients), the peculiar right ventricular repolarization disappeared in 87.7% of the cases (p less than 0.0001). It can be concluded that the peculiar right ventricular repolarization, in presence of main bundle branch block supports the diagnosis of atrial septal defect.

[Echocardiography and trivalvular infectious endocarditis in a heart without apparent previous cardiopathy]. / Ecocardiografía y endocarditis infecciosa trivalvular en corazón sin aparente cardiopatía previa.

The echocardiographic findings in a patient with infective endocarditis are reported. There was involvement the aortic, mitral, and tricuspid valves. The heart had no previous valvular disease. The M-Mode and two dimensional studies, showed presence of vegetations in the aortic, mitral, and tricuspid valves. We consider that the echocardiogram allows the detection of endocarditis in its early stage.

[Importance of various myocardial factors in "primary" congestive cardiomyopathies]. / Importancia de algunos factores miocardiopáticos en las cardiomiopatías congestivas "primarias".

Thirty one cases of congestive cardiomyopathy previously diagnosed as "idiopathic" were retrospectively studied in order to determine the prevalence of the following pathologic myocardial factors (MFs): severe alcoholism (A), systemic arterial hypertension (SAH) and obstructive coronariopathy (OC). Sixteen (51%), 14(45%) and 9(29%) cases had an association with A, SAH and OC, respectively. Any of these MFs was present in 48% of cases, 2 of them in 19% and 3 in 13% of cases. Some peculiarities of the clinical findings, a particular interpretation of such findings by the attending physician and a modification of the psychological status of some patients were the main causes which prevented the recognition of these MFs. Besides, 67% of the cases had at least one of the following "minor" factors which contributed to the myocardial damage: mitral insufficiency, pulmonary embolism, atrial-ventricular block and diabetes mellitus. A careful investigation of these MFs should be done before a diagnosis of idiopathic congestive cardiomyopathy is considered. In some cases there is more than one pathogenic factor.

[Cardiac damage in Takayasu's arteritis. Study in 125 patients]. / Daño cardíaco en la arteritis de Takayasu. Estudio en 125 pacientes.

In order to asses the importance of cardiac damage in Takayasu's arteritis, 125 cases were studied and followed for 5.8 +/- 5.5 years. The arterial lesion involved the aorta and the principal abdominal branches in 10.4% of cases. Isolated lesions of the supraaortic vessels were present in 25.6% of cases. The rest of cases had obstructions in both arterial territories (64%). Cardiac damage was present in 82.4% of cases with the following manifestations: precordial murmurs (65%), cardiac enlargement (70%), heart failure (28%), angor pectoris (13.6%), abnormal electrocardiogram (60%): left ventricular hypertrophy (40.8%), right ventricular hypertrophy (8.8%) and conduction defects (12%). Aortic regurgitation secondary to enlargement of the aortic root was seen in 11.2%. Mitral incompetence due to left ventricular enlargement was documented in 13.6% of cases. In 2 patients rheumatic heart disease was associated to Takayasu's arteritis. Mortality was 4.8%; mostly due to congestive heart failure. The high incidence of cardiac damage was attributed to systemic arterial hypertension secondary to renovascular obstructions or coarctation of the aorta. Aortic and mitral regurgitation, pulmonary hypertension, and coronary arterial lesions contributed to cardiac damage.

[Double outlet of the right ventricle with anterior aorta to the left of the pulmonary artery in situs solitus]. / Doble cámara de salida de ventrículo derecho con aorta anterior e izquierda en situs solitus.

Two cases of double outlet of the right ventricle with an anterior aorta to the left of the pulmonary artery are described. Both in situs solitus. One had an anterior interventricular communication, and other had a middle posterior communication. The importance of the aortic component of the second sound is analyzed with regard to its localization and intensity. An analysis is also made of the morphology of the cardiac silhouette and the peculiarities of the electrocardiogram as diagnostic aides in the malformation. Considerations are made of the distinct theories which explain the malformation. It is clearly shown that a correct diagnosis is necessary since this cardiopathy may be treated surgically.