Jeffrey C. Milliken

Annular abscesses in surgical endocarditis: anatomic, clinical, and operative features

BACKGROUND The aim of this study was to determine patterns of anatomic, clinical, and operative features in surgical endocarditis (SE) with annular abscess (AA). METHODS The study consisted of a retrospective analysis of SE cases with AA between 1981 and 1997. RESULTS A total of 41 cases with AA were found in 106 consecutive SE cases. There was a higher incidence of AA in aortic (37 of 71 [52%]) (p<0.01) compared to mitral (6 of 42 [14.3%]) or tricuspid (0 of 12) infections. However, the mitral abscesses had a greater tendency toward fistula or pseudoaneurysm formation (4 of 6 [67%]) than other valve abscess cavities (7 of 46 [15%]) (p<0.01). Severe heart failure (p<0.01), heart block (p<0.05), and fistula/pseudoaneurysm (p<0.001), were more often found in SE with AA than without. There were 46 separate aortic AA in 37 instances of aortic valve SE. Of these, 31 of 46 (67%) were less than 1 cm (group 1), 10 of 46 (22%) were large but confined to a given cusp annulus (group 2), 4 of 46 (8.6%) were large between multiple cusps (group 3), and 1 of 46 (2.2%) was circumferential (group 4). There were four instances of aortoventricular discontinuity. Group 1 abscesses were repaired by local closure without a patch significantly more often than the other groups. The mortality of SE with AA was significantly greater for larger AA (groups 3 and 4, 3 of 5 [60%]) than for smaller AA (groups 1 and 2, 0 of 36) (p<0.001). There were six separate mitral AA in six instances of mitral SE, five requiring patch repair. The 30-day operative mortality for AA cases was 3 of 41 (7.3%) compared to 2 of 65 (3.1%) without AA. All AA mortalities involved large AA in the aortic valve position. Of 35 mechanical valves placed for AA, only one required subsequent removal for prosthetic endocarditis. CONCLUSIONS Annular abscesses are most frequent in aortic AA, but fistulas/pseudoaneurysms are more frequent in mitral AA. Small to moderate aortic AA can be managed by local closure without an increased mortality compared to SE without AA. Patients with large aortic AA have a higher operative mortality. Mechanical prostheses are safe and effective for the majority of patients with AA.

Underuse of Coronary Revascularization Procedures: Application of a Clinical Method ☆

OBJECTIVES Our main objective was to apply a new method to determine whether coronary revascularization procedures are underused, especially among African-Americans and uninsured patients. BACKGROUND Although overuse of revascularization procedures has been studied, underuse as defined clinically has not been examined before. METHODS The study was conducted at four public and two academically affiliated private hospitals in Los Angeles; 671 patients who underwent coronary angiography between June 1, 1990 and September 30, 1991 and met explicit clinical criteria for coronary revascularization were included. The main outcome measure was the proportion of patients undergoing an indicated procedure within 12 months (ascertained by medical record review and confirmed with a telephone survey). Adjusted relative odds of undergoing an indicated procedure for African-Americans and patients in public hospitals compared with whites and patients in private hospitals were calculated. RESULTS Overall, 75% of patients underwent a revascularization procedure. Of 424 patients requiring bypass surgery, 107 angioplasty and 140 either bypass surgery or angioplasty, 59%, 66% and 75% underwent the procedure, respectively. African-Americans were less likely than whites to undergo operation (adjusted odds ratio [OR] 0.49, p < 0.05) and angioplasty (adjusted OR 0.20, p < 0.05). Patients in public hospitals were less likely than those in private hospitals to undergo angioplasty (adjusted OR 0.10, p < 0.005). CONCLUSIONS Underuse of coronary revascularization procedures is measurable and occurs to a significant degree even among insured patients attending private hospitals. Underuse is especially pronounced among African-Americans and patients attending public hospitals. Future cost-containment efforts must incorporate safeguards against underuse of necessary care.

Imaging of Patent Foramen Ovale with 64-Section Multidetector CT

PURPOSE To investigate the feasibility of 64-section multidetector computed tomography (CT) by using CT angiography (a) to demonstrate anatomic detail of the interatrial septum pertinent to the patent foramen ovale (PFO), and (b) to visually detect left-to-right PFO shunts and compare these findings in patients who also underwent transesophageal echocardiography (TEE). MATERIALS AND METHODS In this institutional review board-approved HIPAA-compliant study, electrocardiographically gated coronary CT angiograms in 264 patients (159 men, 105 women; mean age, 60 years) were reviewed for PFO morphologic features. The length and diameter of the opening of the PFO tunnel, presence of atrial septal aneurysm (ASA), and PFO shunts were evaluated. A left-to-right shunt was assigned a grade according to length of contrast agent jet (grade 1, <or=1 cm; grade 2, >1 cm to 2 cm; grade 3, >2 cm). In addition, 23 patients who underwent both modalities were compared (Student t test and linear regression analysis). A difference with P < .05 was significant. RESULTS A flap valve, seen in 101 (38.3%) patients, was patent at the entry into the right atrium (PFO) in 62 patients (61.4% of patients with flap valve, 23.5% of total patients). A left-to-right shunt was detected in 44 (16.7% of total) patients (grade 1, 61.4%; grade 2, 34.1%; grade 3, 4.5%). No shunt was seen in patients without a flap valve. Mean length of PFO tunnel was 7.1 mm in 44 patients with a shunt and 12.1 mm in 57 patients with a flap valve without a shunt (P < .0001). In patients with a tunnel length of 6 mm or shorter, 92.6% of the shunts were seen. ASA was seen in 11 (4.2%) patients; of these patients, a shunt was seen in seven (63.6%). In 23 patients who underwent CT angiography and TEE, both modalities showed a PFO shunt in seven. CONCLUSION Multidetector CT provides detailed anatomic information about size, morphologic features, and shunt grade of the PFO. Shorter tunnel length and septal aneurysms are frequently associated with left-to-right shunts in patients with PFO.

Aortic saddle embolus. A twenty-year experience.

Clinical experience with aortic saddle embolus (ASE) is not extensive due to the relative infrequent lodging of emboli at the aortic bifurcation. During the period 1962–1982, 26 patients (mean age, 56 years) were treated at the UCLA Medical Center for ASE and followed from 2 to 158 months (mean, 45 months). These cases were reviewed in order to identify features of diagnosis, anticoagulation, and operation which impact on results. All 26 patients presented with bilateral lower extremity ischemia with or without extension of clot to the iliac bifurcation. Ninety-six per cent of emboli were of cardiac origin and one-third occurred in patients who had previous symptoms of chronic lower extremity ischemia. Rest pain and motor/sensory deficits were main complaints in 92% of the patients, but did not become manifest until more than 6 hours, unlike more distal emboli which have an earlier presentation. Preoperative angiography, even in the patient with a history of claudication, has a small role in planning the surgical approach to patients with ASE and, although performed in 11 patients, it influenced operation in only two. Operation within the “golden period” of 6 hours after embolization did not significantly influence outcome after ASE, since 20 patients were operated on more than 6 hours after embolization, with results similar to six patients who were operated on less than 6 hours after embolization. Early high-dose heparinization, used in all patients and maintained for a mean of 12 days, may have contributed to this effect. In 22 patients (85%) Forgarty catheter extraction via bilateral groin approaches was used with a mortality of 14%; only one death was directly attributed to the catheter embolectomy. In 15% of patients, a direct approach on the aorta was selected with a zero mortality rate. Postoperative functional result was excellent with an amputation rate of only 2% (one limb). Re-embolization occurred in seven patients (27%) after discharge, five of whom had not been maintained on Coumadin™ and two who were not anticoagulated adequately. The authors conclude that the keys to successful treatment of ASE include high dose heparin which is maintained through the perioperative period, embolectomy without pre-oprative angiogrphy, and maintenance of long-term oral anticoagulation.

Ascending aortic dissection in weight lifters with cystic medial degeneration

We report 4 cases of ascending aortic dissection in patients with long histories of weight lifting. In 2 of the patients, the initial symptoms of dissection developed while they were lifting weights. Two patients had a history of hypertension and 2 had previously used anabolic steroids. All 4 were successfully treated surgically. Histopathology showed aortic medial changes in all 4. We believe that the hemodynamic stresses of weight lifting, namely, a rapid increase in systemic arterial blood pressure without a decrease in total peripheral vascular resistance, in combination with aortic medial degeneration may have contributed to the development of the aortic dissection.

Ex vivo cardiac allograft preservation by continuous perfusion techniques.

The current technique of cardiac preservation for clinical transplantation by infusion of cold cardioplegia and immersion of the heart in an isotonic saline bath at 4°C limits safe tissue preservation time to 4 to 6 hours. The myriad of benefits to be gained by extending cardiac preservation time has prompted the search for alternatives to hypothermic immersion of the heart, the most promising of which involves techniques of coronary artery perfusion. Countless studies have shown the benefits of long-term storage of donor hearts by perfusion rather than the immersion technique. Continuous perfusion preservation has three basic advantages over simple immersion. Perfusion preservation with oxygen carrying solutions has the advantage of preventing ischemia, anaerobic metabolism, and reperfusion injury. Second, nutritional supplementation and provision of substrate can be more effectively delivered to myocardial cells. Third, continuous perfusion preservation effects the clearance of metabolic waste products from the coronary circulation. The composition of the ideal perfusion solution and optimal preservation conditions remain incompletely defined.

ALK F1174V mutation confers sensitivity while ALK I1171 mutation confers resistance to alectinib. The importance of serial biopsy post progression.

Many acquired resistant mutations to the anaplastic lymphoma kinase (ALK) gene have been identified during treatment of ALK-rearranged non-small cell lung cancer (NSCLC) patients with crizotinib, ceritinib, and alectinib. These various acquired resistant ALK mutations confer differential sensitivities to various ALK inhibitors and may provide guidance on how to sequence the use of many of the second generation ALK inhibitors. We described a patient who developed an acquired ALK F1174V resistant mutation on progression from crizotinib that responded to alectinib for 18 months but then developed an acquired ALK I1171S mutation to alectinib. Both tumor samples had essentially the same genomic profile by comprehensive genomic profiling otherwise. This is the first patient report that demonstrates ALK F1174V mutation is sensitive to alectinib and further confirms missense acquired ALK I1171 mutation is resistant to alectinib. Sequential tumor re-biopsy for comprehensive genomic profiling (CGP) is important to appreciate the selective pressure during treatment with various ALK inhibitors underpinning the evolution of the disease course of ALK+NSCLC patients while on treatment with the various ALK inhibitors. This approach will likely help inform the optimal sequencing strategy as more ALK inhibitors become available. This case report also validates the importance of developing structurally distinct ALK inhibitors for clinical use to overcome non-cross resistant ALK mutations.

MDCT of the S-Shaped Sinoatrial Node Artery

OBJECTIVE The purpose of this study was to use 64-MDCT to investigate the anatomic characteristics of the S-shaped variant of the sinoatrial node (SAN) artery and to describe the clinical implications of the findings in ablative procedures involving the left atrium. MATERIALS AND METHODS Coronary CT angiograms of 250 patients (152 men, 98 women; mean age, 60 +/- 12 [SD] years) were retrospectively analyzed for identification of the origin, number, anatomic course, mode of termination, and S-shaped variant of the SAN artery. RESULTS At least one SAN artery was detected in 244 patients. The S-shaped variant was seen in 35 (14.3%) of these patients. Thirty-four of the variants (30.6% of all left SAN arteries) arose from the proximal to middle portion of the left circumflex artery (mean distance between the ostium of the left circumflex artery and the origin of S-shaped variant, 28.7 +/- 13.1 mm). The other variant (0.7% of all right SAN arteries) originated from the distal right coronary artery. The S-shaped variant was the only artery supplying the SAN in 28 (11.4%) of the patients. In patients with two arteries supplying the SAN, the right SAN artery and the S-shaped variant of the left SAN artery were seen together in seven patients. The S-shaped SAN artery (mean distance from atrial wall, 2.43 +/- 0.992 mm) had a predictable proximal course, lying in the posterior aspect in a groove between the orifices of the left superior pulmonary vein and the left atrial appendage close to the left atrial wall. The terminal segment of the artery approached the nodal tissue posterior to the superior vena cava in 22 patients, anterior to the vena cava in 10 patients, and through branches surrounding the vena cava in two patients. CONCLUSION The S-shaped variation of the SAN artery is common and has a characteristic anatomic course. MDCT can be used to plan surgical and catheter-based left atrial interventions in which this artery is at risk of injury.

Postoperative Thrombotic Thrombocytopenic Purpura After Open Heart Operations

BACKGROUND Postoperative thrombotic thrombocytopenic purpura (pTTP) after cardiovascular operations has an alarmingly high mortality rate if untreated. Five patients after coronary artery bypass graft (CABG) procedure were diagnosed with pTTP when they were observed to have a persistent thrombocytopenia associated with symptoms of fever, renal insufficiency, thromboembolic events, or altered mental status in conjunction with a microangiopathic hemolytic anemia (MAHA). A guideline for early diagnosis, followed by timely treatment in these cases, is reviewed. METHODS A retrospective record review of postoperative patients with thrombocytopenia identified 5 patients that met the criteria for pTTP from 2004 to 2008. We examined these 5 cardiovascular surgical patients in terms of clinical presentation, laboratory data, and outcomes. RESULTS All patients had the combination of an unexplained thrombocytopenia (platelets < 50,000 mm(3)) in conjunction with a MAHA as determined by the presence of schistocytes. Symptoms of neurologic dysfunction and renal insufficiency developed in all patients. Thromboembolic events were noted in 1 patient. All patients underwent plasmapheresis. In 3 patients, response time to clinical recovery and normalization of hematologic laboratory values after plasmapheresis was 3, 4, and 8 days. Two patients did not recover and died. One patient had a clinical and laboratory recovery after 19 days of plasmapheresis; however, after 11 days, thrombocytopenia with MAHA developed and he died on day 53 from complications related to the operation. CONCLUSIONS Postoperative TTP should be recognized as a possible pathophysiologic mechanism for unexplained postoperative thrombocytopenia and treatment should be initiated once the diagnosis is established.

Reduction aortoplasty for moderately sized ascending aortic aneurysms.

Abstract  Enlargement of the ascending aorta may coexist with concomitant valvular, coronary, or other cardiac diseases. If dilation is moderate (i.e., < 6 cm diameter) and another cardiac procedure is being performed, we have reduced the diameter of the ascending aorta with an S‐shaped incision and excision of the curves of the “S” as a modified Z‐plasty. We have performed the procedure in 23 patients with concomitant procedures including aortic valve replacement in 21 (1 as a pulmonary autograft), coronary bypass in 1, and resection of subaortic stenosis in 1. There were 15 males and 8 females with a mean age of 53 years (range 8–67 years). The mean maximal pre‐operative diameter on transesophageal echocardiography was 5.0 ± 0.7 cm (range 3.2–6.6 cm). The mean intraoperative postreduction diameter was 3.1 ± 0.6 cm (range 2.1–4.1) (p < 0.01). All patients tolerated their procedures well. Sixteen patients were studied by transthoracic echocardiography postoperatively. These patients had a mean intraoperative postreduction diameter of 2.9 ± 0.65 cm that increased to 3.1 ± 0.45 cm (p = NS) after a mean follow‐up of 9.9 ± 12.6 months. Of these, seven patients were studied > 1 year postoperatively. Their mean intraoperative postreduction diameter of 2.9 ± 0.5 cm increased to 3.1 ± 0.35 cm (p = NS) after a mean follow‐up of 22.1 ± 9.2 months. No known recurrences of the aneurysms have occurred. We feel this technique is valid in patients with moderate aortic dilation undergoing concomitant cardiac procedures and in whom more aggressive aortic interventions are not warranted.