Fulminant myocarditis successfully treated with a left ventricular assist device: a case report

A previously healthy 28-year-old woman was admitted under a diagnosis of acute myocarditis. Six hours after admission, circulatory support using intraaortic balloon pumping and percutaneous cardiopulmonary support were introduced, because uncontrollable ventricular arrhythmia appeared unexpectedly. Subsequently, decreased peripheral platelet count appeared, in spite of improved hemodynamics. Therefore, a left ventricular assist device was implanted and she was weaned from the percutaneous cardiopulmonary support. On the fifth postoperative day, she was successfully weaned from the left ventricular assist device with full recovery of myocardial function. Myocardial biopsy demonstrated the appearance of acute viral myocarditis. This case suggests that the left ventricular assist device might offer effective circulatory support for acute fulminant myocarditis.     

Long-term mechanical ventricular assistance toward myocardial recovery

Myocardial recovery after VAD support provides a perfect example of reverse remodeling. It also establishes that heart failure may not be an end of the road situation. Although post-LVAD myocardial recovery has become a distinct entity, basis of reversal of the dedifferentiation process will need to be further explored. With this objective, several centers in the United States have formed the LVAD Working Group to: determine the incidence of myocardial recovery; obtain serial studies to determine the response of the LVAD-supported heart to stress; and study the tissue and serological changes as they relate to the recovery process. Patients enrolled in this study will receive anti-heart failure therapy and serial examinations after implantation and explanation. Stress evaluations will include dobutamine stress echocardiograms as well as bicycle exercise with right heart catheterization. A large database of prospectively collected data will likely result in a greater understanding of myocardial recovery and the LVAD weaning process.     

Direct mechanical ventricular assistance during ventricular fibrillation

A technique of direct mechanical ventricular assistance (DMVA) has been available since 1966. Ventricular assistance is provided by a glass cup lined with a Silastic diaphragm. It is held on the cardiac ventricles by suction. Alternating positive and negative pressure in the space between the cup and the diaphragm provides a pumping mechanism for blood flow. DMVA was compared to closed chest massage (CCM) and open chest massage (OCM) during ventricular fibrillation in six dogs. Each technique was applied for 10 minutes. Three dogs had CCM followed by OCM and then DMVA. Three dogs had only OCM and DMVA. Blood pressure and cardiac output were measured. All variables were calculated as a percentage of pre-ventricular-fibrillation values. Mean blood pressure was 19.7% with CCM, 39.8% with OCM, and 55.1% with DMVA. Systolic blood pressure was 25.8% with CCM, 51.9% with OCM, and 64.0% with DMVA. Diastolic blood pressure was 17.3% with CCM, 37.3% with OCM, and 48.9% with DMVA. Cardiac output was 13.8% with CCM, 37.1% with OCM, and 58.0% with DMVA. For each variable, OCM produced statistically higher values than did CCM. DMVA produced statistically higher values than did OCM for all variables. These preliminary results suggest that DMVA may be superior to currently available methods of cardiac massage during ventricular fibrillation.     

Fulminating myocarditis: myocardial recovery after circulatory assistance

The clinical expression of acute myocarditis is variable from paucisymptomatic to fulminating forms which are usually lethal within days. The latter presentation takes the form of very acute cardiac failure. During this phase, the severity of myocardial dysfunction may be such that death ensues. However, if the patient survives, paradoxically, these forms have a better long-term prognosis with complete recovery of myocardial function being possible after the acute phase. The authors report a typical case of fulminating myocarditis with electromechanical dissociation, which recovered completely after a period of circulatory assistance. This case illustrates the rapidity of deterioration of the haemodynamic status and the importance of organ dysfunction despite early management. In a review of the literature, the authors found about 150 reported cases of acute myocarditis treated with circulatory assistance. In the best series, about half the patients were weaned off the circulatory assistance without having to undergo cardiac transplantation. However, the potential recovery of myocardial function is difficult to predict.     

Sawfish left ventricle: acute myocarditis presenting with left ventricular aneurysm

A 41-year-old female patient with no previous history of cardiovasculardisease nor cardiovascular risk factors was admitted to theemergency department for typical     

Saphenous vein graft flow during left ventricular assistance with an axial-flow pump

The effects of continuous-flow support on bypass graft flow have not been quantified clinically. Continuous-flow left ventricular assist devices unload the left ventricle throughout the cardiac cycle, which narrows pulse pressure and converts passive left ventricular filling during diastole to active flow throughout the cardiac cycle. We report the case of a 63-year-old man with severe congestive heart failure who underwent coronary artery bypass grafting and was supported with an axial-flow pump. In this patient, saphenous vein graft flow during left ventricular assistance provided adequate coronary perfusion.     

Right ventricular function in an operating room model of mechanical left ventricular assistance and its effects in patients with depressed left ventricular function

Approximately 20% of patients who receive left ventricular assist devices (LVADs) for refractory cardiac failure after open heart surgery have had complications of right ventricular failure. To evaluate this problem in the diseased heart we simulated an LVAD in the operating room by bypassing and unloading the left ventricle with the heart-lung machine before routine open heart surgery. Right ventricular function was assessed in 12 patients with preoperative left ventricular ejection fractions of less than 0.55 (poor left ventricular function) (mean +/- SEM 0.40 +/- 0.03) and 10 patients with ejection fractions greater than 0.55 (normal left ventricular function) (0.63 +/- 0.02). Measurements before and during left ventricular bypass in the normal left ventricular function group revealed no change in cardiac output (from 5.7 +/- 0.6 to 5.8 +/- 0.4 liters/min), with a decrease in right ventricular end-diastolic pressure (from 8 +/- 2 to 6 +/- 1 mm Hg). However, in the poor left ventricular function group, cardiac output was increased significantly during left ventricular bypass from 4.5 +/- 0.2 to 5.3 +/- 0.4 liters/min and right ventricular end-diastolic pressure was decreased significantly from 13 +/- 2 to 8 +/- 2 mm Hg. During bypass there were significant reductions in mean pulmonary arterial pressure from 17 +/- 3 to 10 +/- 2 mm Hg in the normal left ventricular function group and from 27 +/- 3 to 12 +/- 2 mm Hg in the poor left ventricular function group. These measurements reflect passive changes in pulmonary pressures due to reductions in left ventricular filling pressure during left ventricular bypass.(ABSTRACT TRUNCATED AT 250 WORDS)     

Thrombotic occlusion of an aortic-root xenograft during left ventricular assistance

A 45-year-old man underwent repair of a congenital bicuspid aortic valve and complex aortic-root aneurysm with an aortic-root xenograft. A CentriMag® left ventricular assist device was implanted for cardiac support and was subsequently replaced with a HeartMate II® left ventricular assist device. A day later, the patient was returned to the operating room for control of bleeding, and thrombotic occlusion of the prosthetic aortic valve was detected. The patient underwent thrombus removal, oversewing of the prosthetic valve, and bypass of the left anterior descending coronary artery. This case emphasizes the hazard of bypassing a failed left ventricle with a cardiac assist device after aortic valve replacement, even with a bioprosthesis.Key words: Aorta/surgery, aortic arch/surgery, aortic root/surgery, aortic valve replacement, heart valve prosthesis, postoperative complications, thrombosis, ventricle assist devicesPostcardiotomy support with a left ventricular assist device (LVAD) after aortic valve and aortic root replacement presents a unique challenge. Even in the presence of a prosthetic aortic valve, aortic-root stasis can result in valve thrombosis. We describe the case of a patient who had thrombosis of an aortic-root xenograft during LVAD support after undergoing repair of a complex aortic aneurysm.     

Improvement of left ventricular mechanical dyssynchrony associated with restoration of left ventricular function in a patient with fulminant myocarditis and complete left bundle branch block

A 52-year-old woman with fulminant myocarditis had completed left bundle branch block (LBBB) and severely impaired left ventricular (LV) function. Marked mechanical dyssynchrony with septal-to-posterior delay of 389 ms was observed by echocardiographic speckle tracking radial strain imaging on admission, which was dramatically improved to 106 ms after total recovery from acute myocarditis with restoration of LV ejection fraction whereas her electrocardiogram still showed complete LBBB.     

Characterization of left ventricular mechanical function during arrhythmias with two dimensional echocardiography: I. premature ventricular contractions

Two dimensional echocardiography was applied experimentally in the closed chest dog to quantitate left ventricular function during and immediately after single premature ventricular contractions induced through threshold stimulation at the apex. Coupling intervals were varied over a range from 35 to 85 percent of the R-R interval during normal sinus rhythm (920 to 980 ms). The quality of tomographic echocardiographic images during premature as well as postextrasystolic beats was found to be satisfactory for quantitating short axis section areas at end-diastole and end-systole. A systolic fractional area change was computed from two dimensional echocardiographic measurements to characterize mid ventricular cardiac function, which correlated significantly with peak left ventricular pressure and maximal first derivative of left ventricular pressure (dP/dt). Marked shortening of coupling intervals reduced fractional shortening during premature systole and enhanced the degree of potentiation during the postextrasystolic beat. By contrast, premature beats with relatively long coupling intervals caused less reduction in contraction and only minor postextrasystolic potentiation.Systolic shortening of left ventricular length as well as transverse diameters were studied in a two dimensional echocardiographic long axis cross section. During long coupling intervals contraction was normal except for distinct regional systolic outward “bulging” in the apical region. In contrast, short coupling intervals were associated with a more significant generalized derangement of ventricular wall motion during systole. It is concluded that the two dimensional echocardiographic method can be used to portray and quantitate global as well as regional left ventricular function during disturbances of cardiac rhythm.     

Pediatric mechanical circulatory assistance. Biventricular assistance for fulminant myocarditis in a 5 year old child

The authors report the case of a 5 years old infant with cardiogenic shock due to a fulminant myocarditis. The severity of the shock which was refractory to conventional therapies necessitated to require to a cardiopulmonary bypass on emergency, followed by an external pneumatic bi-ventricular assistance. After 10 days (3 days with cardioplumonary bypass and 7 days of bi-ventricular assistance), the patient had been able to be disconnected of any mechanical circulatory supply with total recovery of the cardiac function.     

Severe transient left ventricular "hypertrophy" occurring during acute myocarditis

We report an unusual sequence of echocardiographic abnormalities observed during the course of acute myocarditis in a young woman. Striking left ventricular "hypertrophy" transiently followed the normalization of marked segmental wall motion abnormalities. These rapid and marked alterations in left ventricular wall thickness suggest that myocardial inflammation and edema resulted in the transient appearance of myocardial hypertrophy. Our findings also indicate that contractility may be nonhomogeneously depressed in acute myocarditis.     

Right and left ventricular flow during mechanical alternans

Pulmonary and aortic blood flow simultaneous with right and left ventricular isometric tension were measured in anesthetized dogs during mechanical alternans induced by rapid atrial driving. It was found that any steady state of mechanical alternation can be altered to another steady state by a single premature or delayed beat. The relationship between the force of the alternating beats was not necessarily equal in the two ventricles. Pulmonary and aortic flow changed markedly with changing steady states of mechanical alternation, at the same heart rate, within wide range of flow levels. Moreover, inequality between the mechanical alternation of the two ventricles was at times associated with disparity of aortic and pulmonic flow. The possible mechanism and clinical significance have been mentioned.     

Acute myocarditis with thrombus near left ventricular outflow tract

A young woman presented with fulminant heart failure. Transthoracic echocardiography revealed severe left ventricular dysfunction with a mass adjacent to the basal anterior wall, near the left ventricular outflow tract (LVOT). The cause of the acute heart failure and mass was unclear. Transesophageal echocardiography, with contrast, and cardiac magnetic resonance imaging findings were consistent with thrombus near the LVOT. Cardiac biopsy suggested giant cell myocarditis. The patient was treated with anticoagulation, steroids, and heart failure medications with resolution of the thrombus. This case was remarkable for the location of thrombus at the base of the ventricle.     

Servocontrolled cardiac assistance: effects of left ventricular to aortic and left atrial to aortic assistance on infarct size.

Devices for cardiac assistance are effective in supporting the falling circulation. In this study the effect of left ventricular to aortic assistance in salvaging ischemic myocardlum was evaluated in dogs and compared with the effect of left atrlal to aortic assistance. In a control group, there was good correlation between measurements of infarct size obtained with S-T segment mapping at 20 minutes, trlphenyl tetrazollum chloride staining at 5 hours and determination of the distribution of radioactive mlcrospheres (P < 0.01). A Servocontrolled roller pump used to control pump speed according to left atrlal pressure allowed reduction of left ventricular pressure to 38 percent of systemic levels and provided stable bypass for prolonged periods. The pressure-time index was reduced to 37 percent of baseline levels (P < 0.005). A reduced infarct size, as measured with S-T segment mapping and triphenyl tetrazollum chloride staining, was observed in Group II, dogs given left ventricular to aortic assistance before occlusion of the left anterior descending coronary artery (P < 0.05), and in Group III, dogs given assistance 20 minutes after occlusion (P < 0.05). Left atrlal to aortic assistance did not reduce infarct size in this model. Electron microscopic studies confirmed the infarct distribution. Blood flow distribution measured with use of radioactive mlcrospheres showed that in the ischemic area endocardial/eplcardial ratio increased with left ventricular assistance; in the control group and with left atrlal assistance the ratio decreased with the second occlusion (P < 0.05). Left ventricular to aortic assistance is thus superior to left atrial to aortic assistance in ability to salvage ischemlc myocardlum. The Servocontrolled roller pump offers an effective, simple method of postoperative cardiac assistance.     

Usefulness of percutaneous left ventricular assist device as a bridge to recovery from myocarditis

The TandemHeart percutaneous left ventricular assist device is a left atrial-to-femoral artery bypass system that can be implanted percutaneously within 30 minutes and provides active circulatory support. The TandemHeart has been used mainly for temporary hemodynamic assistance during high-risk coronary interventions and postcardiotomy heart failure. This report describes initial experience with this device as a successful bridge to cardiac recovery in 3 patients with acute myocarditis. All patients presented with severe cardiogenic shock (mean cardiac index 1.1 L/min/m2), and end-organ perfusion could not be maintained despite intra-aortic balloon counterpulsation and the maximal use of vasopressive agents. The patients were successfully bridged to myocardial recovery with the TandemHeart (mean duration of support 5 days, range 2 to 8). The only complication was a short episode of ventricular fibrillation during device placement in 1 patient, which did not result in any morbidity or mortality. All patients were discharged home (mean duration of stay 15 days). In conclusion, the TandemHeart proved to be a safe and effective bridge to myocardial recovery in these patients with acute myocarditis.     

Acute severe cardiac failure complicating myocardial infarction. Experience with 100 patients referred for consideration of mechanical left ventricular assistance.

One hundred patients were referred with suspected acute cardiac failure following acute myocardial infarction. The diagnosis was confirmed in 72: 31 of these patients underwent elective medical treatment, with 2 survivors (6%); 41 were accepted for counter pulsation, but 9 died before this could be initiated and another 2 died shortly after vain attempts to pass the balloon catheter were abandoned; 30 patients underwent counterpulsation with 14 hospital survivors (47%). Survivor status was usually good. Results of counter pulsation were better in patients who were not shocked (with 5/5 survivors) than in those who were in shock (with 9 of 25 survivors). Results support the view that counterpulsation (alone or combined with corrective surgery) may play an important role in the complications of myocardial infarction provided intervention is early.     

Young patients with nonischemic cardiomyopathy have higher likelihood of left ventricular recovery during left ventricular assist device support

BackgroundRecovery of ventricular function during left ventricular assist device (LVAD) support allowing device explantation occurs infrequently. We explored the hypothesis that certain patient profiles are more likely to exhibit LV recovery during LVAD support.Methods and ResultsA retrospective analysis of data from the HeartMate II bridge to transplant (BTT) and destination therapy (DT) trials was conducted, including 490 BTT, 600 DT, and 18 compassionate-use patients. Of the 1,108 patients, 20 (1.8%; 10 BTT, 10 DT) were explanted owing to LV recovery. The median age was 33 years, and 12 patients (60%) were <40 years of age. History of heart failure was <1 year for 11 patients (61%), and the primary etiology was nonischemic (90%). Of the patients with nonischemic etiologies and <1-year history of heart failure, 13% were explanted. Three patients required LVAD reimplantation; of the remaining 17, 16 remain alive. At follow-up (median 510 days), the mean ejection fraction was 42% (20%–67%) and the mean left ventricular end-diastolic diameter was 55 ± 8 mm. At the 2-year follow-up (n = 13), patients were New York Heart Association functional class I or II and overall survival rate was 85 ± 11%.ConclusionsThe results of this study suggest that LV recovery is most likely to occur in young patients (<40 years) with nonischemic cardiomyopathy of <1 year duration. Two-year postexplant survival was excellent.