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Featured researches published by Alvaro Montoya.


The Annals of Thoracic Surgery | 1989

Ventricular aneurysm due to blunt chest injury

John Grieco; Alvaro Montoya; Henry J. Sullivan; Mamdouh Bakhos; Bryan K. Foy; Bradford M. Blakeman; Roque Pifarré

A left ventricular aneurysm developed in 3 patients sustaining blunt chest injury. Evidence of an acute myocardial infarction on the electrocardiogram and enzyme analysis prompted cardiac catheterization, which revealed total occlusion of the left anterior descending coronary artery in 2 of the 3 patients. Ventricular aneurysmectomy was performed in each patient. A review of the literature revealed 32 previously reported patients with left ventricular aneurysm caused by blunt trauma. Clinical features, catheterization or autopsy findings, and outcome are examined.


The Annals of Thoracic Surgery | 1987

Aortic Valve Replacement in Patients 75 Years Old and Older

Bradford M. Blakeman; Roque Pifarré; Henry J. Sullivan; Alvaro Montoya; Mamdouh Bakhos; John Grieco; Bryan K. Foy

A consecutive group of 100 patients in the eighth decade of life who had aortic valve replacement (AVR) from 1975 through 1986 were retrospectively studied. Eighty-five of them were in New York Heart Association (NYHA) Functional Class III or IV. Isolated AVR was performed in 44 patients and AVR with concomitant procedures, in 56. Perioperative mortality (30 days) was 3%, and perioperative morbidity included 83 complications in 60 patients. Long-term follow-up was available on 93 patients, 71 of whom were alive and 22 of whom were dead. Sixty-eight of the 71 long-term survivors are now in NYHA Class I or II. The low rate of perioperative mortality and the improved quality of life after AVR support the performance of this procedure in this older population.


The Annals of Thoracic Surgery | 1987

Early Myocardial Revascularization for Postinfarction Angina

Robert N. Jones; Roque Pifarré; Henry J. Sullivan; Alvaro Montoya; Mamdouh Bakhos; John Grieco; Bryan K. Foy; Jay Wyatt

In 1983 and 1984, coronary artery bypass grafting (CABG) was performed on 107 consecutive patients for postinfarction angina. In each instance, CABG was done within 30 days of infarction. Sixty-three patients (59%) required intravenous administration of nitroglycerin and/or the intraaortic balloon pump (IABP) for relief of angina. Oral medications relieved angina in the remaining 44 patients. Thirty-eight patients underwent CABG 7 days or less after the infarction (Group 1), 25 received it between 8 and 15 days later (Group 2), and 44 had CABG between 16 and 30 days later (Group 3). There were 9 in-hospital deaths: 4 in Group 1, 2 in Group 2, and 3 in Group 3. Thirteen patients needed the IABP for hemodynamic stability as well as relief of angina. Even when the patient was stable hemodynamically, death was more likely to occur among these 13 patients if CABG was conducted within 7 days of infarction. Follow-up was 94% complete at 29.4 months. Eighty-six percent of patients were asymptomatic or in New York Heart Association Functional Class I, and 6% were in Class II. There were 2 late deaths. CABG for angina can be accomplished within 30 days of an acute infarction with good results. The exception to this rule is the patient in whom shock develops after a myocardial infarction and who, despite stabilization, receives CABG within 7 days of the infarction.


The Annals of Thoracic Surgery | 1996

Arterial impedance in patients furing intraaortic balloon counterpulsation

Shin Y. Kim; David E. Euler; William Jacobs; Alvaro Montoya; Henry J. Sullivan; Vassyl A. Lonchyna; Roque Pifarré

BACKGROUNDnSymptomatic improvement of a patients hemodynamic condition during intraaortic balloon counterpulsation (IABC) is considered to result largely from a reduction in afterload. Afterload can be accurately quantified by arterial input impedance measurements. Here we report the effect of IABC on arterial impedance in humans.nnnMETHODSnTo characterize the effects of IABC on arterial input impedance, impedance measurements were obtained using aortic annulus Doppler flow and pressure from the aortic balloon catheter. Impedance spectra were compared between the cardiac cycles preceding and following the cycle with IABC in 25 patients.nnnRESULTSnIntraaortic balloon counterpulsation increased stroke volume (23%; p = 0.001), reduced myocardial oxygen demand (11%; p = 0.02), and decreased the aortic pressure at the onset of systole (16%; p = 0.001). There was also a decrease in systemic vascular resistance (24%; p = 0.001), characteristic arterial impedance (21%; p = 0.002), and pulse wave reflection (20%; p = 0.006). Linear regression analysis showed that an increase in stroke volume was predicted only by the decrease in systemic vascular resistance (r = -0.81; p = 0.001).nnnCONCLUSIONSnThe reduction in systemic vascular resistance appeared to be the major mechanism by which IABC improved cardiac pumping efficiency. This effect may result from the passive distention of the peripheral vascular bed due to the propagation of the balloon-augmented diastolic pressure through the arterial system.


The Annals of Thoracic Surgery | 1981

Constrictive Pericarditis Following Cardiac Surgery

Philip L. Rice; Roque Pifarré; Alvaro Montoya

Five patients with constriction secondary to pericarditis or membrane formation following cardiac surgical procedures are reported. In 4 of the 5 patients, a postpericardiotomy syndrome developed after the original procedure. Constriction occurred from ten weeks to almost 6 years after the cardiac operation. Clinicians should watch carefully for the delayed onset of constriction in patients with a postpericardiotomy syndrome after cardiac operation.


Journal of Cardiac Surgery | 1988

Perioperative dissection of the ascending aorta : types of repair

Bradford M. Blakeman; Roque Pifarré; Henry J. Sullivan; Alvaro Montoya; Mamdouh Bakhos; John Grieco; Bryan K. Foy

Iatrogenic aortic injury occurring during either coronary bypass grafting or valve replacement is a well‐recognized complication of cardiac surgery. We retrospectively reviewed our experience and found 11 cases occurring in a case load of 8,945 hearts (incidence of 0.12%). All 11 cases were repaired, with 10 patients surviving. The type of repair used usually was determined by when the diagnosis was made. When an intraoperative diagnosis was made, a local repair was done in four of six cases. If a postoperative diagnosis was made, then all five patients needed the ascending aorta replaced. With early diagnosis and rapid repair, good surgical results can be achieved.


The Annals of Thoracic Surgery | 1996

Effect of heartmate left ventricular assist device on cardiac autonomic nervous activity

Shin Y. Kim; Alvaro Montoya; Joseph P. Zbilut; Kwabena Mawulawde; Henry J. Sullivan; Vassyl A. Lonchyna; Mark R. Terrell; Roque Pifarré

BACKGROUNDnClinical performance of a left ventricular assist device is assessed via hemodynamic parameters and end-organ function. This study examined effect of a left ventricular assist device on human neurophysiology.nnnMETHODSnThis study evaluated the time course change of cardiac autonomic activity of 3 patients during support with a left ventricular assist device before cardiac transplantation. Cardiac autonomic activity was determined by power spectral analysis of short-term heart rate variability. The heart rate variability before cardiac transplantation was compared with that on the day before left ventricular assist device implantation.nnnRESULTSnThe standard deviation of the mean of the R-R intervals of the electrocardiogram, an index of vagal activity, increased to 27 +/- 7 ms from 8 +/- 0.6 ms. The modulus of power spectral components increased. Low frequency (sympathetic activity) and high frequency power (vagal activity) increased by a mean of 9 and 22 times of each baseline value (low frequency power, 5.2 +/- 3.0 ms2; high frequency power, 2.1 +/- 0.7 ms2). The low over high frequency power ratio decreased substantially, indicating an improvement of cardiac sympatho-vagal balance.nnnCONCLUSIONSnThe study results suggest that left ventricular assist device support before cardiac transplantation may exert a favorable effect on cardiac autonomic control in patients with severe heart failure.


The Annals of Thoracic Surgery | 1994

Chronic cardiac rejection masking as constrictive pericarditis

Thomas J. Hinkamp; Henry J. Sullivan; Alvaro Montoya; Soon Park; Linda Bartlett; Roque Pifarré

The hemodynamic changes consistent with constrictive pericarditis are often encountered in patients who have undergone cardiac transplantation. We describe here 4 patients who underwent pericardiectomy after cardiac transplantation. All were found to have evidence of a thickened and constricting peel of pericardium at surgical exploration. Their postoperative clinical courses were variable. One patient with primarily effusive constriction experienced marked improvement. Three patients failed to show clinical improvement and had persistently elevated atrial and ventricular end-diastolic pressures. A coexisting restrictive cardiomyopathy secondary to chronic rejection, coronary arteriopathy, or long-standing constriction may have been the cause of this poor outcome. Many patients with transplanted hearts exhibit evidence of poor diastolic ventricular compliance without evidence of classic constriction; some manifest both the restrictive and constrictive components. The careful selection of patients with constrictive pericarditis can optimize the outcome.


The Annals of Thoracic Surgery | 1993

Infective aortic endocarditis after percutaneous balloon aortic valvuloplasty

Soon Park; Alvaro Montoya; Niberto Moreno; John F. Moran; William Jacobs; Roque Piferre

Infective aortic endocarditis developed in an elderly patient after a percutaneous balloon aortic valvuloplasty. The transesophageal echocardiogram demonstrated a perivalvular abscess. The patient underwent surgical replacement of the infected valve, but later succumbed to renal failure. The development of infective aortic endocarditis should be recognized as a potentially fatal complication of percutaneous balloon aortic valvuloplasty. The important measures in preventing bacteremia during percutaneous balloon aortic valvuloplasty and the appropriate role of operation are discussed.


The Annals of Thoracic Surgery | 1982

Technique to Facilitate Mitral Valve Exposure

Roque Pifarré; Samuel Balderman; Henry J. Sullivan; Alvaro Montoya; Mamdouh Bakhos

Abstract We describe a technique to facilitate mitral valve exposure by mobilizing the superior and inferior venae cavae. The intrapericardial cavae are encircled by a cuff of pericardium, which can be freed circumferentially for 4 to 5 cm on the superior vena cava and 2 to 3 cm on the inferior vena cava. This maneuver allows for extensive retraction and elevation of the right atrium and venae cavae, thereby making exposure of the mitral valve much easier, even in those patients with a small atrium.

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Roque Pifarré

Loyola University Medical Center

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Henry J. Sullivan

Loyola University Medical Center

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Mamdouh Bakhos

Loyola University Medical Center

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Bryan K. Foy

Loyola University Medical Center

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John Grieco

Loyola University Medical Center

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Bradford M. Blakeman

Loyola University Medical Center

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Shin Y. Kim

Loyola University Medical Center

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Soon Park

Loyola University Medical Center

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Robert N. Jones

Loyola University Medical Center

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Thomas J. Hinkamp

Loyola University Medical Center

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