Analysis of prosthetic cardiac devices: a guide for the practising pathologist

Abstract

Pathologists all over the world increasingly encounter prosthetic cardiac devices. A good evaluation of these devices is a valuable source of information, which can contribute to patient care and the appreciation and understanding of the pathobiology involved in the changes occurring between the host and the implanted prosthetic device. This article summarises the considerations underlying the analysis of prosthetic devices (particularly prosthetic heart valves), including the identification of the devices, the major morphological features of the devices, their modes of failure, and some technical details about evaluation and pitfalls.

Figure 10

Anteroposterior and lateral x rays of a Carpentier-Edwards porcine bioprosthesis. (C) The flow surface and (D) the non-flow surface of a Carpentier-Edwards porcine valve. The cusps are pliable and intact. However, all three commissural regions show detachment from the stent posts.

Figure 11

(A) The flow surface and (B) the non-flow surface of a Carpentier-Edwards pericardial bioprosthesis. The cusps are soft, pliable, intact, and they co-apt well.

Figure 14

A soft Edwards-Physio annuloplasty ring. It has a soft, synthetic core covered with synthetic fabric.

Figure 16

x Ray of an abdominal aorta shows a large stent in place. The most proximal segment shows an open cone (the rest of the stent is lined by fabric).

Figure 1

Gross examination of prosthetic heart devices: essential steps.

Figure 2

Detailed examination of prosthetic heart valves. *For special investigations only. Adapted from Schoen. CT, computed tomography.

Figure 3

(A) Anteroposterior and (B) lateral x rays of a Starr-Edwards mechanical valve (Model 1000) shows the intact “three leg cage”. (C) Flow surface and (D) non-flow surface of a “four leg cage” Starr-Edwards (Model 6400) valve. The struts are intact and the occluder (or poppet) has a pale yellow/brown colour. The non-flow surface shows tissue (arrows) still adherent to the sewing cuff.

Figure 4

Bjork-Shiley concavo-convex valve. (A) x Ray of profile (lateral) view and (B) anteroposterior view showing the large (inflow) strut and the small (outflow) strut. Gross appearance of the valve; (C) valve partially closed with the disc in the oblique position and (D) valve open (disc or occluder is nearly vertical).

Figure 5

(A) x Ray (anteroposterior) of a Bjork-Shiley Monostrut valve. (B) Outflow surface showing the single outflow strut and (C) inflow surface of the Bjork-Shiley monostrut valve. The struts and the disc are intact.

Figure 6

(A–C) x Rays of a Carbomedics bileaflet valve prosthesis with the discs open, discs closed, and profile of the prosthesis, respectively; x rays also show the radio opaque prosthesis housing. (D) The flow surface (discs open) and (E) the non-flow surface of the Carbomedics bileaflet prosthesis. The flow and non-flow surfaces of the sewing cuff are carbon coated (black).

Figure 7

(A, B) x Rays of the flow surface and profile of the St Jude Medical bileaflet prosthesis. Views of a St Jude Medical bileaflet prosthesis with (C) the leaflets open and (D) the leaflets closed. A thick layer of grey/white pannus is seen on the flow and the non-flow surfaces of the sewing ring.

Figure 8

(A, B) Anteroposterior and lateral x rays of a Hancock porcine valve show a radio opaque valve ring and small eyelets in each of the stent posts. (C) The flow surface and (D) the non-flow surface of the porcine valve. The cusps are soft, pliable, and intact.

Figure 9

Anteroposterior and lateral x rays of an Ionescu-Shiley pericardial bioprosthesis showing the valve ring in three parts. Two of the three cusps show radio opaque areas of calcification (arrows). (C) The flow surface and (D) the non-flow views of an Ionescu-Shiley bovine pericardial valve. Pannus (arrows) is seen on the flow surface.

Figure 12

Early and late postoperative complications of prosthetic heart valves. LV, left ventricle.

Figure 13

A Carpentier-Edwards annuloplasty ring. This D shaped ring has a hard metal core.

Figure 15

x Ray of an aortic arch and descending segment with a stent in place (D). Two of the stent struts show fractured segments (arrow).

Figure 17

(A) An open (no fabric) stent in an aorta that had a co-arctation treated with this stent. (B) An aortic stent or endograft, showing the fabric lining the stent (on its inside (luminal) surface).

Figure 18

A heart obtained at necropsy shows stents in a right coronary artery (arrows). The left coronary artery shows extensive calcification. A Swan-Ganz catheter is seen in the right side of the heart (right atrium, right ventricle, and pulmonary artery).

Figure 19

(A) Segment of coronary artery with a stent in place and embedded in GMMA, sectioned with a special lathe, surface polished, and stained with haematoxylin and eosin. This stent was in place for two weeks. The stent struts (arrows) and their relation to the vessel wall are seen. A minimal tissue reaction is seen focally. (B) This intracoronary stent was in place for seven weeks and was processed in the same manner as the stent in panel A. The stent struts are well placed and a good lumen is still evident. A circumferential tissue reaction is seen. Atherosclerotic plaque, blood clot (C), and calcification (P) are also seen.

Figure 20

Examination of endovascular devices: stents for aortic aneurysm repair.