FORUM-LETTERS
INTRAAORTIC BALLOON THROMBOLYSIS IN AMI
TO THE EDITOR
PUMP AND
To the Editor: We applaud Ohman et al1 regarding their experience with intraaortic balloon counterpulsation in patients receiving thrombolytic therapy. To our knowledge this is only the third report that begins to characterize this topic. 2. 3 As additional support for the reported data, observations from our own experience2 demonstrate a similar in-hospital mortality rate (39%) and vascular complication rate (11%) when compared to the findings of Ohman et al. Some caution should be exercised with regard to comparisons of safety data, however, inasmuch as it appears that many patients in Ohman’s study underwent insertion of an intraaortic balloon pump beyond the point in time when thrombolytic agents would directly influence coagulation parameters and subsequent risk of vascular complications. In addition, definitions of vascular complications appear to be somewhat divergent between reports. Finally, we note with interest the various thrombolytic treatment regimens reported in Ohman’s study. Analysis of our own data suggest significant trends in adverse hematologic complications based on specific selection of individual thrombolytic agents. Data on this aspect are not available from Ohman’s report. Most certainly this is an area of intervention that requires further detailed prospective investigation before definitive statements can be made. However, preliminary reports confirm a favorable impact on morbidity and mortality regardless of the methodology, size, and/or level of specialization of the reporting facility. Alan J. Silverman, DO Diuision of Cardiology Harper Hospital Wayne State University School of Medicine Detroit, MI 48201 Robert W. Wetmore, PharmD Department of Pharmacy Services Botsford General Hospital 28050 Grand River Ave. Farmington Hills, MI 48336 REFERENCES
Ohman EM, Califf RM, George BS, Quigley PJ, Kereiakes DJ, Harrelson-Woodlief L, Candela RJ, Flanagan C, Stack RS, Top01 EJ, and the Thrombolysis and Angioplasty in Myocardial Infarction (TAMI) study group. The use of intraaortic balloon numning as an adiunct to reperfusion therapy in acute myocardial mfa&tion. A& HEART j 1991;121:895-961. Silverman AJ. Williams AM. Wetmore RW. Stomel RJ. Complications of intraaortic balloon counterpulsation insertion in patients receiving thrombolytic therapy for acute myocardial infarction. J Intervent Cardiol 1991;4:49-52. Goodwin M. Hartmann J, Mikeever L, et al. Safety of intraaortic balloon counterpulsation in patients with acute myocardial infarction receiving streptokinase intravenously. Am J Cardiol 1989;64:937-8.
REPLY To the Editor: We appreciate the comments of Drs. Silverman and Wetmore. As noted in our report,’ bleeding complications occur frequently in patients with intraaortic balloon pumping (IABP) after thrombolysis. In a previous report2 we observed that use of IABP is a strong predictor of hemorrhagic complications. It is noteworthy 1720
that the patients who were treated with IABP were the sickest patients, where complications (vascular and hemorrhagic) would be expected to be high. The majority of patients in our report (69%) received tissue plasminogen activator (TPA). The remaining patients received urokinase alone (13%) or in combination with TPA (185 ). The proportions of patients with IABP but without coronary artery bypass grafting who received more than two units of red blood cells were: TPA 20%) urokinase 33%) and combination TPA and urokinase 21%. In view of the small number of patients, no firm conclusion can be drawn from these data. We are currently performing a randomized trial comparing IABP with standard therapy in patients undergoing angioplasty during the acute phase of myocardial infarction. Data from this ongoing study should provide answers to the questions posed by Silverman and Wetmore. E. Magnus Ohman, MD for the TAMI Study Group Duke University Medical Center Box 3151 Durham, NC 27710 REFERENCES
1. Ohman EM, Califf RM, George BS, Quigley PJ, Kereiakes DJ, Harrelson-Woodlief L. Candela RJ. Flanaean C. Stack RS. Top01 EJ, and the Thrombolysis and Angioplasty in Myocar: dial Infarction (TAMI) Study Group. The use of intraaortic balloon pumping as an adjunct to reperfusion therapy in acute myocardial infarction. AM HEART J 1991;121:895-901. 2. Califf RM, Top01 EJ, George BS, Boswick JM, Abbottsmith C, Sigmon KN, Candela R, Masek R, Kereiakes D, O’Neill W, Stack RS, Stump D, and the Thrombolysis and Angioplasty in Myocardial Infarction Study Group. Hemorrhagic complications associated with the use of intravenous tissue plasminogen activator in treatment of acute myocardial infarction. Am J Med 1988;85:353-9.
MIXED VENOUS
OXYGEN
SATURATION
IN AMI
To the Editor: The study by Sumimoto et al.’ detailing the use of mixed venous oxyhemoglobin saturation (SvOz) as a prognostic indicator in acute myocardial infarction (AMI) is of considerable interest. The use of oxygen transport monitoring in AMI, particularly in association with cardiogenic shock (CS), has been suggested previously by various investigators. In 1964 MacKenzie et a1.2 reported the hemodynamic, blood gas, and lactate responses to the administration of high inspired concentrations of oxygen (90 ‘% to 94 % ) in AM1 with and without CS. They showed that by improving arterial oxygenation, and thus oxygen delivery, arterial blood lactate levels could be decreased suggesting an improved oxygen supply/ demand balance. Some years later, and once pulmonary artery catheterization was available as a clinical tool, Da Luz et al3 documented the presence of critical reductions in SvOz in association with hyperlactatemia in CS. Most recently a comprehensive study of oxygen transport variables and their responses to therapy in CS complicating AM1 was published. Creamer et a1.4 showed that the well-defined hemodynamic changes of CS are accompanied by defective oxygen transport as evidenced by low levels of oxygen delivery and very low SvOz levels. Moreover, these investigators showed that a clinical
INTRAAORTIC BALLOON THROMBOLYSIS IN AMI
TO THE EDITOR
PUMP AND
To the Editor: We applaud Ohman et al1 regarding their experience with intraaortic balloon counterpulsation in patients receiving thrombolytic therapy. To our knowledge this is only the third report that begins to characterize this topic. 2. 3 As additional support for the reported data, observations from our own experience2 demonstrate a similar in-hospital mortality rate (39%) and vascular complication rate (11%) when compared to the findings of Ohman et al. Some caution should be exercised with regard to comparisons of safety data, however, inasmuch as it appears that many patients in Ohman’s study underwent insertion of an intraaortic balloon pump beyond the point in time when thrombolytic agents would directly influence coagulation parameters and subsequent risk of vascular complications. In addition, definitions of vascular complications appear to be somewhat divergent between reports. Finally, we note with interest the various thrombolytic treatment regimens reported in Ohman’s study. Analysis of our own data suggest significant trends in adverse hematologic complications based on specific selection of individual thrombolytic agents. Data on this aspect are not available from Ohman’s report. Most certainly this is an area of intervention that requires further detailed prospective investigation before definitive statements can be made. However, preliminary reports confirm a favorable impact on morbidity and mortality regardless of the methodology, size, and/or level of specialization of the reporting facility. Alan J. Silverman, DO Diuision of Cardiology Harper Hospital Wayne State University School of Medicine Detroit, MI 48201 Robert W. Wetmore, PharmD Department of Pharmacy Services Botsford General Hospital 28050 Grand River Ave. Farmington Hills, MI 48336 REFERENCES
Ohman EM, Califf RM, George BS, Quigley PJ, Kereiakes DJ, Harrelson-Woodlief L, Candela RJ, Flanagan C, Stack RS, Top01 EJ, and the Thrombolysis and Angioplasty in Myocardial Infarction (TAMI) study group. The use of intraaortic balloon numning as an adiunct to reperfusion therapy in acute myocardial mfa&tion. A& HEART j 1991;121:895-961. Silverman AJ. Williams AM. Wetmore RW. Stomel RJ. Complications of intraaortic balloon counterpulsation insertion in patients receiving thrombolytic therapy for acute myocardial infarction. J Intervent Cardiol 1991;4:49-52. Goodwin M. Hartmann J, Mikeever L, et al. Safety of intraaortic balloon counterpulsation in patients with acute myocardial infarction receiving streptokinase intravenously. Am J Cardiol 1989;64:937-8.
REPLY To the Editor: We appreciate the comments of Drs. Silverman and Wetmore. As noted in our report,’ bleeding complications occur frequently in patients with intraaortic balloon pumping (IABP) after thrombolysis. In a previous report2 we observed that use of IABP is a strong predictor of hemorrhagic complications. It is noteworthy 1720
that the patients who were treated with IABP were the sickest patients, where complications (vascular and hemorrhagic) would be expected to be high. The majority of patients in our report (69%) received tissue plasminogen activator (TPA). The remaining patients received urokinase alone (13%) or in combination with TPA (185 ). The proportions of patients with IABP but without coronary artery bypass grafting who received more than two units of red blood cells were: TPA 20%) urokinase 33%) and combination TPA and urokinase 21%. In view of the small number of patients, no firm conclusion can be drawn from these data. We are currently performing a randomized trial comparing IABP with standard therapy in patients undergoing angioplasty during the acute phase of myocardial infarction. Data from this ongoing study should provide answers to the questions posed by Silverman and Wetmore. E. Magnus Ohman, MD for the TAMI Study Group Duke University Medical Center Box 3151 Durham, NC 27710 REFERENCES
1. Ohman EM, Califf RM, George BS, Quigley PJ, Kereiakes DJ, Harrelson-Woodlief L. Candela RJ. Flanaean C. Stack RS. Top01 EJ, and the Thrombolysis and Angioplasty in Myocar: dial Infarction (TAMI) Study Group. The use of intraaortic balloon pumping as an adjunct to reperfusion therapy in acute myocardial infarction. AM HEART J 1991;121:895-901. 2. Califf RM, Top01 EJ, George BS, Boswick JM, Abbottsmith C, Sigmon KN, Candela R, Masek R, Kereiakes D, O’Neill W, Stack RS, Stump D, and the Thrombolysis and Angioplasty in Myocardial Infarction Study Group. Hemorrhagic complications associated with the use of intravenous tissue plasminogen activator in treatment of acute myocardial infarction. Am J Med 1988;85:353-9.
MIXED VENOUS
OXYGEN
SATURATION
IN AMI
To the Editor: The study by Sumimoto et al.’ detailing the use of mixed venous oxyhemoglobin saturation (SvOz) as a prognostic indicator in acute myocardial infarction (AMI) is of considerable interest. The use of oxygen transport monitoring in AMI, particularly in association with cardiogenic shock (CS), has been suggested previously by various investigators. In 1964 MacKenzie et a1.2 reported the hemodynamic, blood gas, and lactate responses to the administration of high inspired concentrations of oxygen (90 ‘% to 94 % ) in AM1 with and without CS. They showed that by improving arterial oxygenation, and thus oxygen delivery, arterial blood lactate levels could be decreased suggesting an improved oxygen supply/ demand balance. Some years later, and once pulmonary artery catheterization was available as a clinical tool, Da Luz et al3 documented the presence of critical reductions in SvOz in association with hyperlactatemia in CS. Most recently a comprehensive study of oxygen transport variables and their responses to therapy in CS complicating AM1 was published. Creamer et a1.4 showed that the well-defined hemodynamic changes of CS are accompanied by defective oxygen transport as evidenced by low levels of oxygen delivery and very low SvOz levels. Moreover, these investigators showed that a clinical
