Role of cardiac catheterization in infective endocarditis

Utility and safety of coronary angiography in patients with acute infective endocarditis who required surgery

OBJECTIVES

To assess the benefit/risk ratio to perform a coronary angiography (CA) before surgery for infective endocarditis (IE).

METHODS

We conducted a single-center prospective registry including 272 patients with acute IE intended for surgery and compared patients who underwent a preoperative CA (n = 160) with those who did not (n = 112). A meta-analysis of 3 observational studies was also conducted and included 551 patients: 342 who underwent a CA and 209 who did not.

RESULTS

In our registry, combined bypass surgery (CABG) was performed in 17% of the patients with preoperative CA. At 2 years, the rate of the primary composite end point (all-cause death, new systemic embolism, stroke, new hemodialysis) was similar in the CA (38%) and no-CA (37%) groups. In-hospital and 2-year individual end points were all similar between groups. There were only 2 episodes of systemic embolism after CA and only one possibly related to a vegetation dislodgement. In the meta-analysis, combined CABG was performed in 18% of the patients with preoperative CA. All-cause death was similar in both groups: odds ratio, 0.98 [0.62-1.53], P = .92. Only 5 cases of systemic embolism possibly related to a vegetation dislodgement were reported. New hemodialysis was numerically more frequent in the CA group: odds ratio, 1.68 [0.79-3.58] (18% vs 14%, P = .18).

CONCLUSIONS

In daily practice, two-thirds of the patients with acute IE who required surgery have a preoperative CA leading to a combined CABG in 18% of the patients. Our results suggest that to perform a preoperative CA in this context is not associated with improved prognosis.

Recognition and Treatment of Acute Aortic Regurgitation

Acute aortic regurgitation usually results from infective endocarditis, but is also caused by aortic dissection and trauma to the heart. Most of the left ventricular stroke volume is regurgitated back into the left ventricle; thus, the forward stroke volume to the body and the cardiac output may be severely compromised. An acute increase in left ventricular end-diastolic volume results in a marked increase in left ventricular end-diastolic pressure, and the mitral valve usually closes prematurely. Compensatory tachycardia is the rule and helps to shorten diastole; thus, the time available for aortic regurgitation to occur is reduced, and the cardiac output is often maintained.

On physical examination, there is tachycardia; the peripheral arterial pulse shows a rapid rise, but the systolic pressure is normal; the diastolic pressure is normal or even reduced; and the pulse pressure is often normal. The electrocardiogram (ECG) may be normal except for sinus tachycardia and often for nonspecific ST-T changes. The chest roentgenogram usually shows signs of pulmonary venous hypertension or even pulmonary edema. Echocardiography may show vegetations on the aortic valve, prolapse of an aortic leaflet into the left ventricle, and premature mitral valve closure. Doppler echocardiography is useful in detecting the presence of aortic regurgitation.

In cases of infective endocarditis, the appropriate antibiotic therapy must be given. Aortic regurgitation due to dissection of the aorta is usually an indication for surgery. In patients with severe aortic regurgitation, available medical therapy includes digitalis, diuretics, and vasodilators. When patients respond dramatically to the use of digitalis, diuretics, and arterial dilators, surgical therapy can be delayed until heart failure and infection are controlled and the patient is more stable. If the patient does not respond immediately and dramatically to therapy, then valve replacement should not be delayed, even if the infection is uncontrolled or the patient has had little antibiotic therapy.

Fatal left main coronary artery embolism from aortic valve endocarditis following cardiac catheterization

Coronary artery embolization has been associated with sudden cardiac death. It is more commonly seen with aortic valve endocarditis. It manifests as acute myocardial ischemia or infarction, causing instability of the cardiac rhythm, which may be fatal. We report a patient with aortic valve endocarditis who had sudden cardiac death following coronary angiography. Autopsy revealed embolic occlusion of the left main coronary artery.

Surgical treatment of endocarditis

Since early investigators first suggested that the treatment of endocarditis should include valve replacement for infections not readily controlled with medical therapy alone, the role of surgery has become expanded, yet refined, to improve the outcome of patients with this potentially fatal disease. Innovative surgical techniques have also been developed in an effort to improve the results of surgical treatment for complex sequelae of invasive infections. This article examines the current indications for surgical intervention, compares the various surgical options, and assesses the expected short-and long-term outcome after valve replacement for patients with native valve or prosthetic valve endocarditis.

Propionibacterium acnes causing an aortic root abscess

A case of endocarditis caused by Propionibacterium acnes associated with an aortic root abscess is presented. This supports the current opinion that aortic root abscesses are not necessarily associated with microorganisms of high virulence.

Coronary artery narrowing due to extrinsic compression by myocardial abscess

A case of aortic valve endocarditis complicated by perivalvular abscess extending into myocardium is presented. Echocardiography and aortography failed to detect the abscess, but coronary angiography revealed its presence by extrinsic compression of left anterior descending and diagonal arteries. Morphological features of this rare cause for coronary narrowing are described.

An acquired interatrial fistula secondary to para-aortic abscess documented by transesophageal echocardiography

Para-aortic ring abscess and resulting fistulous communication between adjacent structures frequently occur in prosthetic aortic valve endocarditis but are rarely diagnosed preoperatively. We report a patient who had an abscess involving the aortic-mitral intervalvular fibrosa that eroded into the interatrial septum, causing an interatrial communication with a left-to-right shunt. The abscess was detected by transthoracic echocardiography, but the fistula was only seen by the subsequent transesophageal echocardiogram. To our knowledge, this is the first report of an interatrial fistula secondary to a para-aortic valve abscess and its diagnosis preoperatively. Transesophageal echocardiography should be performed in any patient suspected to have complicated aortic endocarditis.

Evaluation of an aortic annular pseudoaneurysm by MRI: comparison with echocardiography, angiography and surgery

Nuclear magnetic resonance imaging (MRI) was clinically useful in a case of aortic annular pseudoaneurysm complicating bacterial endocarditis. The MRI findings were proven by angiography and surgery. Although surgical correction was attempted, the aneurysm recurred and has been followed by MRI and two-dimensional echocardiography. In addition to two-dimensional echocardiography, MRI represents a useful noninvasive imaging method for diagnosis and follow up of aortic annular pseudoaneurysm.

Nonbacterial thrombotic endocarditis: a review

The entity of NBTE is reviewed in this article. Historic aspects, epidemiology, and pathogenesis are discussed. The clinicopathologic findings are emphasized as well as the potential for antemortem diagnosis and therapy. NBTE is diagnosed infrequently before death. Clinical suspicion is aroused in patients with an underlying process such as malignancy, DIC, or a spectrum of other diseases and evidence of pulmonary and/or systemic embolization. Systemic infection must be excluded. Two-dimensional echocardiography can be utilized to confirm the diagnosis. Anticoagulation therapy with heparin may prevent embolization.

Patch closure of aortic annulus mycotic aneurysms

Twenty-three patients with bacterial endocarditis and mycotic aneurysms of the aortic annulus were treated between 1978 and 1985. There were 18 men and 5 women ranging from 24 to 72 years old. All patients had congestive heart failure and positive blood cultures as a complication of the endocarditis and were in New York Heart Association (NYHA) Functional Class III or IV. The aneurysm complicated late prosthetic valve endocarditis in 7 patients and native valve endocarditis in 16. The most common infecting organisms were streptococci (12 patients) and staphylococci (7 patients). The noncoronary sinus was the most frequent site for aneurysm formation. Following debridement of the abscess cavity, the orifice of the aneurysm was closed with a patch of Dacron in 20 patients and autologous pericardium in 3. A prosthetic valve (18 bioprosthetic and 5 mechanical) was secured to the noninfected portion of the native annulus and to the patch at the level of annulus. There were 3 deaths, 1 perioperative and 2 late, each without evidence of residual infection or aortic insufficiency. There are 20 late survivors (87%). After a mean follow-up of 1 year, all patients are in NYHA Functional Class I. Patch closure of mycotic aneurysms involving the aortic annulus permits aggressive debridement of the abscess cavity and affords closure of the orifice without tension. The prosthetic valve can be seated at the level of the native annulus, thus avoiding complicated reconstructive procedures of the aortic root and coronary arteries. This technique is an effective alternative in selected cases of mycotic aneurysms involving the aortic annulus.

Heart block during bacterial endocarditis: a review of the literature and guidelines for surgical intervention

The management of patients with bacterial endocarditis complicated by atrioventricular block is based on uncontrolled data, mostly from retrospective surgical and autopsy series. It is difficult to advance broad recommendations on the basis of such a biased population. Nevertheless, it is the firm opinion of many experienced clinicians that heart block developing as the result of aortic endocarditis signals myocardial abscess formation, and thereby is an indication for early surgery. I present a patient with aortic and mitral endocarditis in whom first degree heart block developed and then disappeared over five days; she was successfully managed with medical therapy alone. This case illustrates that some patients with endocarditis and heart block will not require surgery. In this setting, I propose the following guidelines in selecting patients for operation: 1) the observed appearance or progression of heart block; 2) the presence of aortic valve involvement; 3) the persistence of heart block, despite at least one week of optimal antibiotics; and 4) the elimination of other potential causes of conduction abnormalities.

The preoperative evaluation in patients with endocarditis. Is cardiac catheterization necessary?

We retrospectively compared clinical assessment and cardiac catheterization to subsequent surgical findings with regard to specific valvular involvement, hemodynamic status, and presence of myocardial abscess in patients recommended for cardiac surgery for endocarditis. Of 105 consecutive patients with endocarditis, 19 met one or more of the following criteria suggesting the need for early surgery: congestive heart failure; systemic emboli; persistent infections or new conduction abnormalities. Of these 19 patients, seven had prosthetic cardiac valves. Clinical assessment was highly sensitive (95 percent) and specific (89 percent) for specific valvular involvement and was also highly sensitive and specific in evaluating myocardial abscess and congestive heart failure; however, clinical assessment could not identify the source of infection in one patient with multiple prosthetic valves, did not define the specific valve in one patient with right-sided endocarditis, and overestimated the severity of mitral regurgitation in one patient who had normal pressures and flows at catheterization. Catheterization incorrectly predicted multivalvular involvement in four patients. At catheterization, only one patient experienced evidence of clinical deterioration, and this was probably not related to the procedure. We conclude that although clinical assessment is correct in most patients, it may on occasion lead to an erroneous conclusion. Catheterization and angiograms are of value in the preoperative evaluation of patients with endocarditis, particularly in cases where the clinical assessment is ambiguous or uncertain. The procedures can be performed at low risk, and the information obtained may substantially influence management in some cases.

Analysis of surgical versus medical therapy in active complicated native valve infective endocarditis

From 1972 to 1980, 23 patients (Group A) with native valve infective endocarditis underwent surgical intervention, often for multiple indications, during the active stage of the infective process because of progressive class III and IV (New York Heart Association) heart failure (12 patients), persistent severe hypotension (3 patients), uncontrolled infection for over 21 days (11 patients), aortic root abscess (2 patients), and pericarditis (1 patient). Eighty-five patients (Group B) with active native valve endocarditis, matched for severity of illness, were treated medically. Two patients (9%) in Group A and 43 patients (51%) in Group B died during the hospital admission (p less than 0.001). Any difference in long-term cumulative survival rate between the 2 groups was largely due to the beneficial impact of surgical management on the hospital mortality. Of 23 patients in Group A, 11 (48%) had an entirely uncomplicated postoperative course. Long-term mortality rates in those with aortic valve endocarditis treated medically (79%) were significantly higher than in those with mitral valve involvement (47%) (p less than 0.05). Patients with aortic valve involvement treated surgically had a better hospital (p less than 0.005) and long-term (p less than 0.0005) survival rate than those treated medically. Two groups at risk for postoperative complications were identified; 3 of 11 patients (27%) with uncontrolled infection had an early postoperative recurrence, and 4 of 7 patients (57%) with an aortic root abscess had postoperative prosthetic paravalvular regurgitation. Surgery therefore effects a substantial reduction in hospital mortality in patients with complicated active infective endocarditis (9% versus 51%), but patients with preoperative prolonged periods of uncontrolled infection or with aortic root abscess are liable to postoperative complications.

Clinical, echocardiographic, and operative findings in active infective endocarditis

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Culture-negative infective endocarditis

Culture-negative endocarditis is not uncommon; the most frequent causes of the culture negative state are prior antibiotic therapy and problems with or inadequacies in bacteriologic technique. In addition to blood culture, studies that can aid in substantiating a presumptive diagnosis of infective endocarditis include echocardiography. Immunologic tests, and cardiac catheterization. Empiric antibiotic therapy often is necessary and should not be delayed to await positive blood cultures and results of antimicrobial sensitivity studies.

Operative techniques in infective endocarditis

Twenty-six of 163 patients with infective endocarditis treated between 1969 and 1979 required operation. The consequences of infection in these 26 patients included leaflet destruction, annular "ring" abscess, fistula formation with ventricular and atrial septal perforation, and myocardial abscess with heart block. Surgical principles used to repair these abnormalities successfully were excision of necrotic tissue, valve replacement, repair of annular defects, and closure of perforations. Temporary and permanent cardiac pacing were used also. The operative mortality was 13%.