Cardiac injuries

Historical perspective

Cardiac injuries have been described since ancient times. The earliest descriptions of a cardiac injury are found in the Iliad and in the Edwin Smith Papyrus , written in approximately 3000 bc . Hippocrates stated that all wounds of the heart were deadly. Ambrose Paré, the famous French trauma surgeon, described two cases of penetrating cardiac injuries, both detailed from autopsy studies. Wolf, in 1642, was the first to describe a healed wound of the heart, and Senac, in 1749, concluded that although all wounds of the heart were serious, some wounds might heal and not be fatal. Larrey was the first to describe the surgical approach to the pericardium to relieve a pericardial effusion and is credited with pioneering the technique for pericardial window. Billroth, in 1875 and in 1883, proclaimed his strong resistance to any attempt at cardiac injury repair. Block, in 1882, created cardiac wounds in a rabbit model and was successful in achieving repair, thus demonstrating successful recovery and suggesting that the same techniques could be applicable to humans. Also, Del Vecchio demonstrated cardiac injury healing after suturing the heart in a canine model.

The first attempt at repairing a cardiac injury was carried out by Axel Hermansen Cappelen ( Table 1 ), a 37-year-old staff surgeon of the Surgical Department A at the National Hospital in Christiania, the old name for Oslo, on September 4, 1895. The patient was a 24-year-old man who sustained a stab wound (SW) to the left chest and was found conscious at his home. The patient was subsequently brought by cab to the hospital and evaluated by Cappelen. What follows is a translation of selected excerpts of Cappelen’s original report published in a Norwegian journal in 1896.

“The young man was brought by cab to the National Hospital in Christiania [now Oslo] in severe shock. He was unconscious on arrival at the hospital, with no palpable pulses. After the administration of ‘Kamferinjektioner’ the patient regained consciousness, a palpable pulse and respiratory rate of 44. There was no blood protruding from the wound, no sucking of air on respiration, and the wounds were dressed.” Initially, the patient was observed. But after significant bleeding was noted from the chest wound, the patient became pulseless. Promptly, Cappelen performed a left thoracotomy at the fourth intercostal space, entering the left hemithoracic cavity and evacuating 1400 mL of blood. Surgical findings were partly coagulated blood in the pericardial sac, and a 2-cm laceration of the left ventricle, with fresh bleeding from a larger artery. “Both the ventricular laceration and bleeding artery were sutured with Chromic-catgut material, on which the bleeding stopped. The operation was performed under chlorophorm anesthesia.” Postoperatively, the patient had tachycardia with weak pulse, which responded to 600 mL of natrium chloride solution administered subcutaneously. Although the patient was conscious, “he felt weak, but did not report.” Additional supportive care consisted of injections of morphium and digitalis (on the second postoperative day, dose not reported). On September 7 (postoperative day 3), the patient got weary, developed a fever (38.6° C), and became increasingly tachycardic (132 beats/minute). He died later that morning from sepsis. Technically speaking, his cardiac repair was a success, although the patient did not survive. In March 1896, Farina, in Rome, made a second attempt to suture a human heart wound of the left ventricle and was unsuccessful.

Success awaited the attempt by Rehn of Frankfurt, Germany, who, on September 9, 1896, successfully repaired a SW of the right ventricle, on a 22-year-old man who had been stabbed in the left fourth interspace and rapidly developed a left hemothorax and was admitted “in extremis” (see Table 1 and Figure 1 ). “There remained one question: what was injured-the heart or its great vessels, an intercostal artery or the internal mammary . . . ? The tract of the wound lay in the direction of the heart. I decided to attempt to arrest the bleeding.”

Surgical findings included 1.5-cm wound of the right ventricle that was hemorrhaging. The wound was digitally controlled and closed with three silk sutures. “It was very disquieting to see the heart pause in diastole with each pass of the needle. . . . The heart gave a labored beat and then resumed with forceful contractions as we breathed a sigh of relief.”

Rehn presented his findings on April 22, 1897, at the German Surgical Congress, introducing his work apologetically, but culminating his presentation with enthusiasm. This new event marked the beginning of cardiac surgery. For the first time, surgeons successfully repaired a cardiac injury in a living heart. This landmark gave birth to the field of cardiac surgery, and these cases were followed by an explosion of techniques to apply in the management of cardiac injuries.

Median sternotomy, one of the most widely used incisions in cardiac injury management, was described by Duval as a median thoracolaparotomy. The ingenuity required to overcome surgical inabilities in draining and restore negative intrathoracic pressure after opening the chest resulted in development of several different surgical approaches to the heart. These included the quadrangular flap with an external hinge, which included two to five cartilages, developed in 1900 by Fontan, from France.

Most unfortunately, the accomplishments of two Americans surgeons who first repaired wounds of the pericardium did not surface until much later. Credit should be given to Dalton, of St. Louis, who, on September 6, 1891, successfully repaired a wound of the pericardium. Also remarkable was the accomplishment of Williams, who, on July 9, 1893, successfully sutured a pericardial laceration in a patient who sustained a SW that penetrated the substance of the myocardium. Because the myocardial wound was not bleeding, it was not sutured. This accomplishment remained obscure, perhaps because neither surgeon described his operation in the literature until some years later. In the case of Williams, his report was published 35 years later in an obscure journal and titled, “Stabwound of the heart and pericardium-suture of the pericardium-recovery- patient alive three years afterward.” Some purist surgeons reported that the pericardium was not the heart. To quote Lillehei, “The paramount fact is, that over 90 years ago two surgeons independently had the courage of their convictions and ventured into a totally unchartered territory. There is glory enough for both and with their work, cardiac surgery made its first beginnings, particularly in America.”

As European reports began to emerge, interest was soon to develop in America by Hill, who, in 1900, collected 17 cases from the world literature, supporting a 59% mortality.

On September 14, 1902, in Montgomery, Alabama, Hill became the first American surgeon to successfully suture a cardiac injury and the first to successfully repair a left ventricular wound in a 13-year-old boy. This case was remarkable in that this operation was performed by the flickering lights of two kerosene lamps on an old kitchen table.

Duval described the median sternotomy incision, and Spangaro, in 1906, described the left anterolateral thoracotomy incision. Rehn continued his interest in cardiac injury management and in 1907 reported a series consisting of 124 patients and a 60% mortality rate. In 1907, the well-known Austrian surgeon Sauerbruch described a method for controlling hemorrhage from a wound of the heart by obstructing flow of blood by compression of its base. “With the right hand the apex of the heart is displaced anteriorly while the third finger of the left hand is inserted through the great transverse sinus, and the fourth and fifth fingers are placed posteriorly in the pericardial cavity. Included between the third and fourth fingers are the venae cava with a part of the right auricle and the pulmonary veins. By compression of these structures the flow of the blood into the ventricles can be controlled. The thumb and index finger of the left hand are free to steady the heart while the wound is sutured.” This became known as the “Sauerbruch grip,” which was poorly tolerated and often resulted in iatrogenic and ventricular fibrillation.

Rudolph (Rodolfo) Matas, a surgeon of Spanish ancestry born in the United States and one of the founders of the American Surgical Society, warned of the dangers of rapidly relieving pericardial tamponade, resulting in exsanguinating hemorrhage. Peck, in his June 4, 1909, presentation to the American Surgical Association, described a survivor of a SW to the right atrium and tabulated the world’s literature on cardiac injuries, presenting 158 cases. Peck disputed the excessive mortality attributed to wounds of the “atria,” which were considered by most surgeons to be more lethal than ventricular wounds. In his review of the literature, he reported on 11 patients, 7 of whom survived, for a mortality of 36.3%.

Peck also reported the combined mortality rate of cardiac wounds as 64% while describing a comprehensive surgical approach consisting of anesthesia, local preparation of the operative field, choice of method for exposure, temporary control of hemorrhage during suturing, and finally, stimulation and resuscitation. His techniques of cardiorrhaphy are still widely used today. At the same time, he pointed to the need for expediency in executing the previously mentioned operative plan. Meanwhile Vaughn, also in 1909, reported a series of 150 patients with a 65% mortality.

In 1912, Pool collected additional patients, added to Peck’s series, and contributed further descriptions of surgical techniques for the management of cardiac injuries, concluding that “[t]he treatment of heart wounds should be surgical.” He also recommended that in suspected wounds of the heart, when the diagnosis is probable but not positive, exploration should be performed. In his study, he described and analytically criticized different surgical approaches and quoted Borchardt, who provided supporting evidence that “[t]he classic heart syndrome of tamponade, due to elevated intrapericardiac pressure is more often absent than present.”

Surgeons during the early part of the century preferred to approach the heart in an extrapleural fashion to minimize the dangers of pneumothorax, but such approaches were time-consuming. To circumvent this problem, Pool recommended using positive-pressure ventilation during anesthesia to prevent pneumothoraces and allowing a rapid transpleural approach to the heart. He also described the use of a fine petroleum jelly-like silk as a suture of choice and defined the indications for pericardial drainage.

Ballance, in 1920, delivered the Bradshaw Lecture on surgery of the heart. To this date, it remains one of the most comprehensive treatises in cardiac injury management. In this prestigious lecture, Ballance summarized the currents of thought present in the surgical literature of that time. In 1923, Smith developed a comprehensive plan for cardiac injury management and for the first time pointed out the dangers of dysrhythmias during cardiac manipulation. He described the use of an Allis clamp near the apex to stabilize and hold the heart to facilitate suturing and also to displace it out of the pericardium for inspection of its posterior surface. Similarly, Smith tabulated and analyzed the mortality of cardiac injuries according to the chambers injured.

Beck, in 1926, described the physiology of cardiac tamponade and reported the results of his animal studies. He described the clinical symptomatology of pericardial tamponade in the triad that now carries his name. In addition, he traced the historical developments of cardiac injury management throughout history while comprehensively describing techniques still in use today. He advocated placing an apical suture to hold the heart under gentle traction before placement of the definitive sutures to affect the repairs.

Similarly, Schoenfeld, in 1928, and Bigger, in 1939, reported their collective experiences in the management of cardiac injuries. In 1941, Elkin was a strong proponent of operative management of cardiac injuries, recommended fluoroscopy to assess cardiac motion, and alerted surgeons to the dangers of ice pick injuries while critically analyzing the advantages and disadvantages of median sternotomy versus left anterolateral thoracotomy incisions. He is also responsible for using a clamp to control hemorrhage from atrial wounds. Beck, in 1942, indicated the necessity of a sparing ligation of coronary arteries in wounds adjacent to these structures and recommended that mattress sutures be placed underneath the bed of the coronary arteries. In 1942, after reviewing the experience with cardiac injury management during World War I, Turner pointed to the need for the emergency treatment of cardiac injuries, particularly those caused by shell fragments.

Beck, in 1942, described the technique of placing mattress sutures under the bed of the coronary arteries. During the same year, Griswold described his experiences and assigned cause of death from cardiac injuries as either exsanguination or tamponade. They recommended rapid intravenous fluid administration, including blood transfusions, but believed that this was of little help in the management of pericardial tamponade, pointing instead to the need for evacuation and aggressive repair of the injury. They described refinements of techniques used to manage cardiac injuries and recommended placement of a small patch of pectoral muscle to partially cover transected coronary arteries. Griswold’s most important recommendation was that “every large general hospital should have available at all times a sterile set-up of instruments and linens, and the operating room with at least one nurse and orderly in attendance, to be open twenty four hours a day.” This statement set the stage for the development of modern-day trauma centers.

In 1943, described the use of pericardiocentesis for managing cardiac injuries in American soldiers during World War II. They proposed nonoperative management of these wounds. They observed that some wounds of the heart may seal spontaneously and stop bleeding on their own. This treatment was advocated in the hope of decreasing the high mortality of these injuries. “The mortality rate in those reported cases in which the patients reached the hospital and were operated on its almost 50% . . . [T]he question arises whether the sum total of successful end results will not be greater if a more conservative policy in regard to immediate operation is adopted in those instances in which there is not active bleeding through the chest wound or into the pleural cavity.” Their protocol included aspiration of blood from the pericardium by the costoxiphoid route, with one further attempt in case of recurrence, and finally, cardiorrhaphy for a second recurrence. This became the standard treatment for many cardiac injuries during World War II. Elkin, in 1944, recommended administration of intravenous infusions before operation and pointed to the beneficial effects of increasing blood volume and in turn, cardiac output. In 1946, drawing on his experience in the management of thoracic injuries during World War II, Harken described techniques to remove foreign bodies adjacent to the heart and major blood vessels. In this daring, series, Harken reported 134 patients requiring 139 operations to remove mediastinal missiles. “A more precise breakdown in the distribution of these missiles is as follows: pericardial, 26; involving pericardium but principally pulmonary, 17; intracardiac, 13; on great vessels (and in walls), 35; intra-vascular (3 embolic), 7; on great vessels but principally pulmonary, 17; mediastinal but not directly on great vessels, 19; a total of 134, with no deaths.” This series is truly remarkable because 13 missiles were intracardiac and all were removed without the benefit of cardiopulmonary bypass.

Since World War II there have been numerous contributions to the field of penetrating cardiac injuries; they can only be briefly covered. Beall, in 1961, first proposed that patients experiencing cessation of cardiac action undergo emergency department (ED) thoracotomy and open cardiac massage. In another publication, in 1962, Beall reported the benefits of cardiopulmonary bypass in managing selected intracardiac injuries such as aortoarterial, aortoventricular, and traumatic atrioseptal and ventriculoseptal defects and, in 1966, described the management of cardiac lacerations adjacent to coronary arteries. Beall was the first to describe the technique of ED thoracotomy (see Table 2 ). Other contributions by Beall and coworkers in 1971 included supporting a change in the pattern of surgical management of cardiac injuries and proceeding directly to thoracotomy and cardiorrhaphy without pericardiocentesis. Arom, in 1977, described the modern variation of the subxyphoid pericardial window, which is in use today. Meanwhile, Mattox refined and protocolized ED thoracotomy and cardiorrhaphy, inclusive of the use of emergency cardiopulmonary bypass in the management of these injuries. These hallmark contributions have made it possible for patients sustaining penetrating cardiac injuries to survive today.

Outcomes-oriented studies have been reported by Mattox, Ivatury, and Rohman (see Table 2 ). Both Lorenz and Milham associated physiologic status with survival in patients with penetrating cardiac injuries. Asensio and coworkers reported the first prospective cardiac injury study in the literature and described the Cardiovascular Respiratory Score (CVRS) as a predictor of outcomes. Later, Asensio, in two large prospective studies consisting of 60 and 105 patients, respectively, validated the CVRS components of the Trauma Score, described intraoperative predictors of outcomes, and using stepwise logistic regression analysis, identified factors such as gunshot wound (GSW) exsanguination and restoration of blood pressure as the most predictable variables of mortality, all while correlating mortality and validating the American Association for the Surgery of Trauma Organ Injury Scale (AAST-OIS) for the heart.

Incidence

Feliciano in 1983 described a 1-year experience consisting of 48 cardiac injuries at Ben Taub Hospital in Houston. Mattox in 1989 described a 30-year experience from the same institution reporting 539 cardiac injuries (18 cardiac injuries per year). Asensio reported two prospective consecutive series reporting a total of 165 cardiac injuries in a 3-year period (55 cardiac injuries per year) at Los Angeles County/USC Medical Center in Los Angeles. In 2018, Asensio analyzed the National Trauma Data Bank (NTDB) of the American College of Surgeons, which identified a total of 2016 patients sustaining penetrating cardiac injuries and calculated the national incidence of 0.16% for these injuries. Thus, penetrating cardiac injuries are uncommon and are usually seen only in busy urban trauma centers. Consequently, few trauma surgeons and trauma centers have significant experience with these injuries.

Etiology

In the civilian arena, penetrating cardiac injuries are usually caused by GSWs, SWs, and rarely by shotgun wounds and ice picks. According to a recent review, 63% of all reported cardiac injuries in America are caused by GSWs and 36% are caused by SWs; shotgun and impalement injuries accounted for approximately 1% of these injuries. In the military arena, Rich and Spencer reported 96 cardiac injuries from the Vietnam conflict. Most of these patients sustained injuries from grenade fragments or shrapnel, and a few of these patients were impaled by flechettes.

Clinical presentation

Beck’s triad—muffled heart tones, jugular venous distention, and hypotension—describes the classical presentation of a patient with pericardial tamponade. Kussmaul’s sign, described as jugular venous distention upon inspiration, is another classic sign attributed to pericardial tamponade. In reality, the presence of Beck’s triad and Kussmaul’s sign represents the exception rather than the rule. It is estimated that Beck’s triad is present in only approximately 10% of patients.

The clinical presentation of penetrating cardiac injuries may range from complete hemodynamic instability to cardiopulmonary arrest; in fact, some penetrating cardiac injuries can be very deceptive in their presentation. The clinical presentation of penetrating cardiac injuries may also be related to other factors, including the wounding mechanism; the length of time elapsed before arrival at a trauma center; and the extent of the injury, which if sufficiently large in terms of myocardial destruction will invariably lead to exsanguinating hemorrhage into the left hemithoracic cavity. The presentation of these injuries is also related to blood loss, as patients who lose between 40% and 50% of intravascular blood volume develop cardiopulmonary arrest. The muscular nature of the left ventricle, and to a lesser extent that of the right ventricle, may seal penetrating injuries and prevent exsanguinating hemorrhage, allowing these patients to arrive with some signs of life at a trauma center.

The most unique presentation of a penetrating cardiac injury is pericardial tamponade. The tough fibrous nature, lack of elasticity, and noncompliance of this structure translate to acute rises in intrapericardial pressure leading to compression of the thin wall of the right ventricle, impairing its ability to accept the returning blood volume, resulting in a concomitant decrease in left ventricular filling and ejection fraction. This results in a drastic decrease in cardiac output and stroke volume. The impaired ability to generate both right and left ventricular ejection fractions increases cardiac work and myocardial wall tension. This results in an increase in myocardial volume of oxygen consumption, which cannot be met, leading to myocardial hypoxemia and lactic acidosis.

It is well known that the pericardium is able to accommodate gradual quantities of blood, provided that the rate of hemorrhage is slow and does not cause acute rises in intrapericardial pressures exceeding the right ventricle and subsequently the left ventricle’s ability to fill. Pericardial tamponade can have both deleterious and protective effects. Its deleterious effects can lead to a rapid rise in pericardial pressure and cardiopulmonary arrest, whereas its protective effect will limit extrapericardial hemorrhage into the left hemithoracic cavity, preventing exsanguinating hemorrhage. Moreno, in a retrospective study consisting of 100 patients presenting with penetrating cardiac injuries, reported 77 patients who presented with pericardial tamponade. The authors reported that for patients presenting with pericardial tamponade, the survival rate was much higher—73% versus 11%—thereby ascribing tamponade a protective effect. These findings were statistically significant, leading the authors to conclude that pericardial tamponade is a critical independent factor in patient survival.

Asensio, in a prospective 2-year study reporting 105 patients, failed to find any statistical significance to the presence of pericardial tamponade in terms of survival and was not able to identify it as a critical independent factor for survival. What remains undefined is the actual period of time after which the protective effect of pericardial tamponade is lost and when exactly this transition occurs, causing its adverse effect on cardiac function.

Diagnosis

Management