PubMed Health⌕ Search

SEARCH · PubMed Health

Results for “Counterpulsation”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 379 records · Page 21Linked to original sources

Experience with intraaortic balloon counterpulsation.

An eleven-year experience with intraaortic balloon pumping (IABP) or counterpulsation in 637 patients was analyzed with respect to early and late results. Intraaortic balloon pumping was employed for left ventricular pump failure, for coronary insufficiency, and in association with cardiac operations. Late results were analyzed by follow-up of 283 (93%) of the 304 patients leaving the hospital, and were studied with respect to duration of survival, activity status, occupational status, presence of cardiac symptoms, use of cardiac medications, and presence of lower extremity claudication. Early results were analyzed for hospital survival (304/637 [48%]). Patient complications of IABP included wound infection (1/637 or 0.2%), vascular complications (66/637 or 10.4%), and balloon failure (8/637 or 1.3%). No deaths were attributable to complications of IABP. Survival did not correlate with the duration of IABP. Survival was improved in patients who had revascularization in association with IABP.

Adult↗

The temporal relationship in arterial and venous prostacyclin and thromboxane activity during 24 hours of intraaortic balloon counterpulsation in dogs.

We studied the effects of intraaortic balloon counterpulsation (IABCP) on prostacyclin (PGI2) and thromboxane (TXB2) levels in dogs during 24 hours of 1:1 IABCP or a sham procedure in which the balloon was positioned but left deflated. The arterial PGI2 levels in the IABCP group increased from control values of 95 +/- 20 pg/ml to 268 +/- 95 pg/ml at 1 hour, 429 +/- 95 pg/ml at 4 hours, and 1,884 +/- 532 pg/ml at 24 hours. The arterial PGI2 levels were consistently higher in the IABCP group. Although the TXB2 measurements revealed no significant differences between groups, the IABCP group consistently had a higher level than the sham group. The platelet count in the control group decreased to 45% of baseline levels versus 55% for the IABCP group. We conclude that prolonged IABCP results in either net production of PGI2 or decreased degradation. The correlation between TXB2 and platelet counts is unclear and remains to be defined.

Animals↗

The role of intraaortic balloon counterpulsation in patients undergoing cardiac operations.

Intraaortic balloon counterpulsation (IABC) was used to assist 60 patients undergoing cardiac operations for reasons of acute left ventricular failure (18 patients) or electively for indications in high-risk coronary and valvular heart disease (42 patients). Nine of 18 patients achieved hemodynamic stability when treated for acute perioperative or postoperative cardiogenic shock. Four of these died from problems unassociated with postoperative left ventricular failure and 5 were long-term survivors, indicating a potential salvage of 50%. In 42 high-risk patients, IABC was used electively to control preinfarction angina before operation (21 patients) and prophylactically to prevent postoperative low-output failure in another 21 patients with severe coronary and valvular heart disease. Thirty-nine, or 93%, of these patients survived. There were no deaths in the preinfarction angina group, 1 death in the group with coronary disease and ejection fractions less than 30%, and 2 deaths in those with valvular heart disease and congestive failure. Seven patients developed thrombotic or ischemic complications, but no permanent damage resulted. IABC is an important form of assistance for any patient with preoperative, intraoperative, or postoperative left ventricular failure and adds safety and hemodynamic stability for the high-risk patient with preinfarction angina or poor ventricular function.

Assisted Circulation↗

Ascending aorta insertion of the dual-chambered intraaortic balloon for counterpulsation during cardiac operations.

A patient with left ventricular power failure after aortocoronary saphenous vein bypass was successfully managed by intraaortic dual-chambered balloon counterpulsation through the ascending aorta. This insertion route reverses the orientation of the spherical distal chamber, which inflates early in diastole and partially occludes the aorta. This position achieved an effective augmentation pressure during left ventricular diastole and reduced arterial end-diastolic pressure considerably. The technique of insertion and events at operation and postoperatively are discussed.

Aged↗

Mechanical complications of intra-aortic balloon counterpulsation.

Intra-aortic balloon counterpulsation (IABP) related complications in a heterogeneous group of patients who received an IABP before or after thrombolytic therapy and mechanical revascularization or in the management of refractory unstable angina and myocardial infarction related mechanical complications were evaluated prospectively. Ninety-one patients were enrolled to the study. Mean IABP duration was 4.3+/-2.4 days. While the IABP was in place, three patients (3.3%) had femoral artery emboli, four patients (4.4%) had lower extremity ischemia that resolved after the removal of the balloon, eight patients (8.8%) had groin hematoma requiring blood transfusion (< or =2 units) and four patients (4.4%) had intra-aortic balloon rupture. The relation of several risk factors to groin hematoma requiring < or =2 units blood transfusion, emboli, lower extremity ischemia and to total complications was evaluated. A chi-squared analysis showed that nadroparine use was more often complicated with emboli (P = 0.00005) and ischemic events (emboli and/or lower extremity ischemia) (three patients; 30% of nadroparine group vs. four patients; 4.9% of heparin group, P = 0.005) and hypercholesterolemia (>200 mg/dl) was more often complicated with lower extremity ischemia (P = 0.017). Forward conditional logistic regression analysis did not show any relation between the risk factors identified and emboli, lower extremity ischemia, ischemic events and groin hematoma (P>0.05), but an inverse relation was found between IABP duration and total complications (P = 0.0198). In conclusion, IABP related complications were found to remain unchanged but were not life-threatening and were inversely related to IABP duration and this suggests shorter periods of IABP use whenever possible and one must be cautious to use low molecular weight heparin in patients with an IABP in place.

Aged↗

Preclinical studies of abdominal counterpulsation in CPR.

Abdominal counterpulsation added to standard cardiopulmonary resuscitation improves blood flow in animal models when compared to chest compressions alone. Similar effects can be demonstrated in analog and digital computer models of the circulation. The technique generates both central aortic and central venous pressure pulses, and successful application of the method depends on maximizing the former and minimizing the latter. Proper technique is important in order to generate the largest possible arteriovenous pressure difference.

Abdomen↗

Theoretical advantages of abdominal counterpulsation in CPR as demonstrated in a simple electrical model of the circulation.

Recent animal studies and preliminary clinical observations suggest that the addition of interposed abdominal compressions (IAC) to ventilation and chest compression of standard cardiopulmonary resuscitation (CPR) augments blood flow, blood pressures, and immediate survival. To investigate the physical basis for enhanced circulation during IAC-CPR, we developed an electrical model of the circulation. Heart and blood vessels were modeled as resistive-capacitive networks, pressures as voltages, blood flow as electric current, blood inertia as inductance, and the cardiac and venous valves as diodes. External pressurization of the heart and great vessels, as would occur in CPR, was simulated by application by half-sinusoidal voltage pulses between vascular capacitances and ground. Closed-chest CPR was simulated by pressurization of all intrathoracic capacitances. IAC was simulated by similar pressurization of the inferior vena cava and abdominal aorta, 180 degrees out of phase with chest compression. During simulation of CPR, IAC improved cranial and myocardial perfusion at all levels of chest compression pressure by amounts linearly related to peak abdominal pressure, suggesting that the abdomen can function as a second, independent blood pump during CPR. Brain and heart flow were improved further during simulated vasoconstriction in kidneys, abdominal viscera, and extremities. Based on the fundamental properties of the cardiovascular system represented in the model, abdominal counterpulsation provides a rational basis for flow augmentation during CPR.

Blood Circulation↗

Intra-aortic balloon counterpulsation for cardiogenic shock due to cardiac contusion in an elderly trauma patient.

Blunt thoracic trauma may cause cardiac contusion and cardiogenic shock resistant to inotropic support. The use of intra-aortic balloon counterpulsation (IABCP) as a mechanical means of augmenting cardiac function following cardiac contusion is rare with case reports largely limited to its use in young trauma patients. We describe the case of a frail, 80-year-old woman who suffered cardiac contusion in a motor vehicle crash. She developed cardiogenic shock with electrocardiograph changes, elevated troponin T and severe global dysfunction on echocardiography. She was successfully managed with invasive monitoring, inotropic support and IABCP. This case provides support for aggressive resuscitation even in the very elderly as recovery from severe cardiac contusion may be possible.

Accidents, Traffic↗

Alterations in ultrasonic backscatter during intra-aortic balloon counterpulsation support in patients with acute myocardial infarction.

Alterations of ultrasonic backscatter parameters have been evident in humans with myocardial infarction or ischemia. The backscatter variability could be restored in ischemic or stunned myocardium after reperfusion. The aims of this study were to determinate changes in regional myocardial ultrasonic backscatter during intra-aortic balloon counterpulsation (IABP) support in patients with acute myocardial infarction (AMI), and to evaluate whether backscatter imaging could be a functional guide of IABP support. A total of 9 patients with AMI were investigated during IABP support with a two-dimensional (2-D) ultrasonic backscatter imaging approach for parasternal short-axis view. Coronary angiography was performed in 6 of the 9 patients. A total of 21 vessel territories were studied in different modes of IABP support: 1:1, 1:2 and standby. Restoration of cyclic variation of backscatter after IABP support was demonstrated in 10 vessel territories. Failure of restoration of cyclic variation of backscatter after IABP support was noted in 6 vessel territories with severe coronary lesions (total or nearly total occlusion) or scar tissue. No changes of the ultrasonic backscatter were found in nonischemic vessel territories with patent coronary arteries or TIMI III coronary flow. In addition, the wall motion score did not change significantly with different IABP support. These results suggest that IABP could restore the cyclic variation of backscatter in ischemic myocardium. Myocardial anisotropy may play an influential role in the alterations of ultrasonic backscatter. We propose that ultrasonic backscatter could be a noninvasively functional guide of IABP use in patients with AMI.

Aged↗

Impact of thrombolysis, intra-aortic balloon pump counterpulsation, and their combination in cardiogenic shock complicating acute myocardial infarction: a report from the SHOCK Trial Registry. SHould we emergently revascularize Occluded Coronaries for cardiogenic shocK?

OBJECTIVES: We sought to investigate the potential benefit of thrombolytic therapy (TT) and intra-aortic balloon pump counterpulsation (IABP) on in-hospital mortality rates of patients enrolled in a prospective, multi-center Registry of acute myocardial infarction (MI) complicated by cardiogenic shock (CS). BACKGROUND: Retrospective studies suggest that patients suffering from CS due to MI have lower in-hospital mortality rates when IABP support is added to TT. This hypothesis has not heretofore been examined prospectively in a study devoted to CS. METHODS: Of 1,190 patients enrolled at 36 participating centers, 884 patients had CS due to predominant left ventricular (LV) failure. Excluding 26 patients with IABP placed prior to shock onset and 2 patients with incomplete data, 856 patients were evaluated regarding TT and IABP utilization. Treatments, selected by local physicians, fell into four categories: no TT, no IABP (33%; n = 285); IABP only (33%; n = 279); TT only (15%; n = 132); and TT and IABP (19%; n = 160). RESULTS: Patients in CS treated with TT had a lower in-hospital mortality than those who did not receive TT (54% vs. 64%, p = 0.005), and those selected for IABP had a lower in-hospital mortality than those who did not receive IABP (50% vs. 72%, p < 0.0001). Furthermore, there was a significant difference in in-hospital mortality among the four treatment groups: TT + IABP (47%), IABP only (52%), TT only (63%), no TT, no IABP (77%) (p < 0.0001). Patients receiving early IABP (< or = 6 h after thrombolytic therapy, n = 72) had in-hospital mortality similar to those with late IABP (53% vs. 41%, n = 64, respectively, p = 0.172). Revascularization rates differed among the four groups: no TT, no IABP (18%); IABP only (70%); TT only (20%); TT and IABP (68%, p < 0.0001); this influenced in-hospital mortality significantly (39% with revascularization vs. 78% without revascularization, p < 0.0001). CONCLUSIONS: Treatment of patients in cardiogenic shock due to predominant LV failure with TT, IABP and revascularization by PTCA/CABG was associated with lower in-hospital mortality rates than standard medical therapy in this Registry. For hospitals without revascularization capability, a strategy of early TT and IABP followed by immediate transfer for PTCA or CABG may be appropriate. However, selection bias is evident and further investigation is required.

Aged↗

Aortic counterpulsation may improve late patency of the occluded coronary artery in patients with early failure of thrombolytic therapy.

OBJECTIVES: Using a prospective, randomized design, we tested our hypothesis that the augmentation of diastolic pressure by intraaortic balloon counterpulsation (IABP) would improve the late patency of the occluded coronary artery in patients with early failure of thrombolytic therapy. BACKGROUND: Rescue angioplasty is often performed in patients in whom thrombolysis has failed, although 30% to 60% of the infarct-related arteries that are closed early after thrombolytic therapy will open later with conservative therapy. METHODS: The study included 45 patients in whom thrombolysis had failed, despite treatment with intravenous tissue-type plasminogen activator (alteplase 0.75 mg/kg body weight) delivered over 60 min within 12 h of the onset of symptoms. All patients underwent coronary angiography 60 min after initiation of thrombolytic therapy (baseline), and Thrombolysis in Myocardial Infarction (TIMI) grade 0, 1 or 2 flow was defined as failed thrombolysis. The patients were randomized to groups receiving IABP for 48 h (n = 23) or conservative therapy (n = 22, control subjects) at the end of cardiac catheterization. The late patency of the infarct-related artery, the primary end point of the study, was evaluated 3 weeks after myocardial infarction. Stenosis of the infarct-related artery was measured using a computer-assisted quantitative angiographic system in blinded manner. Data are expressed as mean value +/- SEM. RESULTS: There was no difference with regard to the baseline value for TIMI flow grade between the groups. However, 3 weeks after myocardial infarction, the patients treated with IABP had a significantly higher frequency of TIMI flow grade 3, lower residual percent stenosis and larger minimal lumen diameter of the infarct-related artery than did the control subjects (74% vs. 32%, p < 0.05; 42 +/- 5% vs. 68 +/- 6%, p < 0.01; and 1.6 +/- 0.1 vs. 0.9 +/- 0.2 mm, p < 0.01, respectively). CONCLUSIONS: These findings suggest that in patients with early failure of thrombolytic therapy, IABP may improve late patency of the occluded coronary artery, probably due to augmented perfusion pressure.

Constriction, Pathologic↗

A prospective, randomized evaluation of prophylactic intraaortic balloon counterpulsation in high risk patients with acute myocardial infarction treated with primary angioplasty. Second Primary Angioplasty in Myocardial Infarction (PAMI-II) Trial Investigators.

OBJECTIVES: A large, international, multicenter, prospective, randomized trial was performed to determine the role of prophylactic intraaortic balloon pump (IABP) counterpulsation after primary percutaneous transluminal coronary angioplasty (PTCA) in acute myocardial infarction (AMI). BACKGROUND: Previous studies have suggested that routine IABP use after primary PTCA reduces infarct-related artery reocclusion, augments myocardial recovery and improves clinical outcomes. METHODS: Cardiac catheterization was performed in 1,100 patients within 12 h of onset of AMI at 34 clinical centers. Clinical and angiographic variables were used to stratify patients undergoing primary PTCA into high and low risk groups. High risk patients were then randomized to 36 to 48 h of IABP (n = 211) or traditional care (n = 226). The study had 80% power to detect a reduction in the primary end point from 30% to 20%. RESULTS: There was no significant difference in the predefined primary combined end point of death, reinfarction, infarct-related artery reocclusion, stroke or new-onset heart failure or sustained hypotension in patients treated with an IABP versus those treated conservatively (28.9% vs. 29.2%, p = 0.95). The IABP strategy conferred modest benefits in reduction of recurrent ischemia (13.3% vs. 19.6%, p = 0.08) and subsequent unscheduled repeat catheterization (7.6% vs. 13.3%, p = 0.05) but did not reduce the rate of infarct-related artery reocclusion (6.7% vs. 5.5%, p = 0.64), reinfarction (6.2% vs. 8.0%, p = 0.46) or mortality (4.3% vs. 3.1%) and was associated with a higher incidence of stroke (2.4% vs. 0%, p = 0.03). IABP use did not result in enhanced myocardial recovery as assessed by paired admission to predischarge and 6-week rest and exercise left ventricular ejection fraction. CONCLUSIONS: In contrast to previous studies, a prophylactic IABP strategy after primary PTCA in hemodynamically stable high risk patients with AMI does not decrease the rates of infarct-related artery reocclusion or reinfarction, promote myocardial recovery or improve overall clinical outcome.

Angioplasty, Balloon, Coronary↗

Use of intraaortic balloon counterpulsation in patients presenting with cardiogenic shock: observations from the GUSTO-I Study. Global Utilization of Streptokinase and TPA for Occluded Coronary Arteries.

OBJECTIVES: We sought to examine the use, complications and outcomes with early intraaortic balloon counterpulsation (IABP) in patients presenting with cardiogenic shock complicating acute myocardial infarction and treated with thrombolytic therapy. BACKGROUND: The use of IABP in patients with cardiogenic shock is widely accepted; however, there is a paucity of information on the use of this technique in patients with cardiogenic shock who are treated with thrombolytic therapy. METHODS: Patients who presented within 6 h of chest pain onset were randomized to one of four thrombolytic regimens. Cardiogenic shock was not an exclusion criterion, and data for these patients were prospectively collected. Patients presenting with shock were classified into early IABP (insertion within one calendar day of enrollment) or no IABP (insertion on or after day 2 or never). RESULTS: There were 68 (22%) IABP placements in 310 patients presenting with shock. Early IABP use occurred in 62 patients (20%) and none in 248 (80%). Most IABP use occurred in the United States (59 of 68 IABP placements) involving 32% of U.S. patients presenting with shock. Despite more adverse events in the early IABP group and more episodes of moderate bleeding, this cohort showed a trend toward lower 30-day and 1-year mortality rates. CONCLUSIONS: IABP appears to be underutilized in patients presenting with cardiogenic shock, both within and outside the United States. Early IABP institution is associated with an increased risk of bleeding and adverse events but a trend toward lower 30-day and 1-year all-cause mortality.

Aged↗

Regional blood flow during cardiopulmonary resuscitation with abdominal counterpulsation in dogs.

The addition of abdominal counterpulsation to standard cardiopulmonary resuscitation (AC-CPR) during ventricular fibrillation has been shown to improve cardiac output, oxygen uptake, and central arterial blood pressure in dogs. The present study was performed to determine the effect of AC-CPR on regional blood flow. Regional blood flow was measured with radioactively labeled microspheres during sinus rhythm and during alternate periods of AC-CPR and standard CPR (STD-CPR) in nine dogs anesthetized with pentobarbital. Blood pressures and oxygen uptake were measured continuously. As in previous studies, diastolic arterial pressure was higher (30.8%) during AC-CPR than during STD-CPR, as were cardiac output (24.5%) and oxygen uptake (37.5%). Whole brain and myocardial blood flow increased 12.0% and 22.7%, respectively, during AC-CPR. Blood flow to abdominal organs was not changed appreciably in response to abdominal compression, and postmortem examination revealed no gross trauma to the abdominal viscera. The AC-CPR technique is simple and is easily added to present basic life support procedures. In light of the improvements observed in myocardial and cerebral blood flow, AC-CPR could significantly improve the outcome of CPR attempts.

Abdomen↗

Effective surgical management of high-risk coronary patients using preoperative intra-aortic balloon counterpulsation therapy.

The proportion of high-risk coronary patients submitted to surgical myocardial revascularization (CABG) is steadily increasing. High-risk patients utilize more hospital resources and have a higher procedural cost than low-moderate risk CABG patients. An efficient management is essential to improve outcome and reduce costs. This report entails three study periods. In an initial retrospective study coronary high-risk criteria were established. At least two of the following factors were required: redo CABG, unstable angina, left main stem stenosis greater than 70%, preoperative left ventricular ejection fraction < 0.30 and diffuse coronary artery disease. Poor preoperative cardiac performance was the major contributing factor for poor outcome. Intra-aortic balloon counterpulsation therapy (IABP) was introduced as preoperative therapy. During a second study period prospective randomized studies found preoperative IABP-therapy efficient, significantly improving both preoperative cardiac index (P < 0.0001), decreasing postoperative mortality (P < 0.0001) and morbidity, shorten intensive care unit stay as well as total hospital stay (P < 0.0001). Drug consumption was significantly reduced (P < 0.0001). Optimal timing was found to be 2 h prior to aortic cross-clamping and the therapy was found highly cost-beneficial with an average 36% reduction of the total procedural cost. During a third study period, well beyond any study protocol period, preoperative IABP therapy was again found highly effective with a close to 100% utilization rate in high-risk patients and continuous efficacy with excellent outcome, despite acceptance of sicker patients. During this post-study evaluation period 1/3 of the high-risk patients presented with 4 of the established risk factors. The use of preoperative IABP therapy is therefore highly recommended for high-risk coronary patients undergoing CABG.

Adult↗

Relationships between cerebral blood flow velocities and arterial pressures during intra-aortic counterpulsation.

OBJECTIVE: To determine the effects of intra-aortic counterpulsation (IABP) on cerebral blood flow velocity. DESIGN: Prospective self-controlled study. SETTING: University hospital surgical intensive care unit. PARTICIPANTS: Nineteen cardiac surgical patients requiring perioperative IABP assistance. INTERVENTIONS: Simultaneous recording of transcranial Doppler middle cerebral artery blood flow velocity and arterial pressure in response to changes in the magnitude of augmentation and trigger ratio. MEASUREMENTS AND MAIN RESULTS: Instantaneous cerebral blood flow velocities correlated with arterial pressures during IABP (r = 0.650) at different magnitudes of augmentation and trigger ratios. The increase in arterial pressure during balloon inflation was associated with an increase in cerebral blood flow velocity, and the decrease in arterial pressure in response to balloon deflation was associated with a decrease in cerebral blood flow velocity that was dependent on the magnitude of augmentation. Different magnitudes of augmentation or trigger ratios had no effect on peak systolic cerebral blood flow velocity, mean cerebral blood flow velocity, mean arterial pressure, or the mean velocity-to-pressure ratio. Instantaneous cerebral blood flow velocity to arterial pressure ratios were lowest in response to balloon deflation at the time of pre-ejection. CONCLUSIONS: IABP modified the phasic profile of cerebral blood flow to reflect the arterial pressure waveform without affecting mean cerebral blood flow velocity. Peak systolic cerebral blood flow velocity was maintained in augmented beats despite the decreased systolic arterial pressure associated with afterload reduction. The acute decrease in cerebral blood flow velocity at pre-ejection was balanced by increased cerebral blood flow velocity during balloon inflation in diastole.

Adult↗

Arterial compliance is a main variable determining the effectiveness of intra-aortic balloon counterpulsation: quantitative data from an in vitro study.

Quantitative data concerning the effect of arterial compliance (AC) on the effectiveness of intra-aortic balloon counterpulsation (IABC) are lacking. The main objective of this study was to investigate the relationship between AC and IABC performance. For this purpose we constructed a Windkessel, lumped-element, hydraulic model of the systemic circulation. The model consisted of a left ventricular assist device (LVAD), a compliance chamber, a peripheral resistor and two open reservoirs. Two Datascope Driving systems were used to operate the LVAD and intra-aortic balloon. We studied the effect of arterial compliance on the effectiveness of IABC at different levels of mean pressure (55, 75 and 95 mmHg) and heart rates (80, 100, 120 bpm). Three indices were used to evaluate IABC performance: the reduction of systolic and end-diastolic "arterial" pressure and the augmentation of diastolic pressure, induced by the IABC. A 22% decrease in AC (1.8-1.4 ml/mmHg) lead to a 30-40% increase in the indices of IABC performance, independently from pressure. In conclusion, arterial compliance significantly affects IABC efficacy and it could be considered as a further clinical criterion to decide IABC application.

Aorta↗