Running Head: TECHNIQUES OF CARDIAC SURGERY
Changes in the Techniques of Cardiac Surgery over time
Tiffany V. Williams
Our Lady of the Lake College
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Heart disease is the leading cause of deaths in the United States, affecting all ages and
ethnicities. The most common type of heart disease is Coronary Artery Disease (CAD) which
can lead to heart attacks, heart failure, and dysrhythmias. With heart disease being the leading
cause of deaths, cardiac surgery is among the top five surgeries performed for treatment. Cardiac
surgeries includes, but not limited to, congenital heart disease surgery, coronary artery bypass
grafting (CABG), aortic aneurysm and dissections, aortic valve repair or replacement, mitral
valve repair or replacement, left ventricular assist device (LVAD), and heart transplants. With
new research in medicine and more technology, the techniques have drastically changed
throughout the years and are steadily improving. The following six articles attempt to explore
the rise, the different techniques, and the future of cardiac surgeries.
Over the years, the heart was considered too delicate for operation. Surgeons were frown
upon with the thought of performing heart surgery. “Theodor Billroth, Professor of Surgery in
Vienna, who personally performed the first successful partial gastrectomy for a stomach cancer
and the first laryngectomy, stated that, “Any surgeon who would attempt an operation on the
heart should lose the respect of his colleagues” (Ellis 2011, p.124). In spite of the criticism, a few
daring surgeons took the initiative to further explore cardiac surgery.
Cardiac surgery dates back to the end of the 19th century with the first successful heart
surgery performed by a German surgeon, Dr. Ludwig Rehn in 1896. Rehn operated on a young
man who had been stabbed in the left chest. He successfully opened the chest through the left
fourth interspace, resected the fifth rib, and opened the pericardium. The tear was repaired with
three sutures, each placed and then tied while the heart was relaxed in diastole. (Ellis 2011). In
the years after, Rehn reported at least 124 successful heart surgeries of stab wounds to the heart
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with a 40% rate of recovery. Rehn proved to his colleagues that heart surgery was in fact
possible. Rehn’s success paved the way to explore various levels of heart surgery (Ellis 2011).
In the 1930’s, the rise of the heart-lung machine and the oxygenator took place. Openheart surgery was considered one of the most important medical advances of the 20th century.
Statically, approximately 2,000 surgeries were performed in one day without a lot of difficulty
and low risk. In 1931, the idea of a heart-lung machine was brought forth when Dr. John Gibbon,
working with Dr. Edward D. Churchill, saw a patient die on the operating table when attempting
to remove a massive pulmonary embolus. They imagined that if it were possible to maintain
circulation and oxygenation the patient could have been saved (Braile, D., & Godoy, M. , 2012).
In 1937, following the unsuccessful surgery, Gibbon built a machine capable of maintaining
breathing and circulation in small animals for 30 to 40 minutes. Yet, this machine needed
improvement. Gibbon developed a new machine using roller pumps. This machine maintained
circulation only in cats. It was too small for dogs and was not feasible for humans. In the years
following, Gibbon collaborated with IBM engineers to build a new machine that was specific in
temperature, level, and flow controls. He operated on dogs, and there was a high mortality rate of
80%. During this time, another surgeon, Dr. Clarence Dennis, began to build an oxygenator. The
object of the oxygenator was to make the blood pass through cellulose tubing to oxygenate the
blood. It worked, but the blood was poorly oxygenated and air bubbles or foam formed. Dennis
revised it by using vertical cylinders in the oxygenator. The vertical cylinders would cause the
blood to be oxygenated without forming bubbles. With this new oxygenator he operated again on
dogs, but the outcome was worse. Only nine dogs survived out of 64. The problem was the loss
of plasma, the reduction of leukocytes and platelets, intestinal hemorrhage and ultimately the
death of the animal. Later, another researcher, Dr. Russel M. Nelson showed that these changes
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resulted from contamination of equipment by bacteria (Braile, D., & Godoy, M. , 2012). A team
of Canadian doctors also showed that lowering the temperature at 20 degrees Celsius causing
hypothermia made the oxygen consumption fall to 15% to normal (Braile, D., & Godoy, M. ,
2012). The oxygenator was changed once again using screen disks. This oxygenator was feasible
for human beings, yet there was still a high mortality rate of dogs. In spite of the mortality rate of
dogs, in 195, Dennis and his colleagues used this oxygenator to operate on a six year girl with a
septal defect. The girl died shortly after surgery, yet the oxygenator performed well. This was the
first patient in the world that was operated on while using the heart-lung machine.
Shortly after this unsuccessful surgery, Dr. C. Walton Lillehei, appointed Associate
Professor of Surgery at the University of Minnesota, developed the concept of the azygos flow.
This procedure would call for the two vena cavas to be clamped for no longer than 40 minutes in
order to maintain function to the brain and other vital organs. With this, he developed a simple
extracorporeal circuit, which used a lobe of the lung to oxygenate blood flow similar to the
azygos vein, allowing operation of dogs without mortality (Braile, D., & Godoy, M. , 2012). He
also suggested the use of hypothermia. Prior to the use of the azygos flow technique, the use of
the hypothermia was being experimented by Dr. F. John Lewis and Mansur Taufic in
Minneapolis. They operated on 10 dogs to correct atrial septal defect. They used the hypothermia
technique of lowering body temperature to 20 degrees Celsius and only one dog died. In 1952,
Lewis and his colleagues used the azygos flow technique and the hypothermia technique to
operate on a five year girl with atrial septal defect. The girl’s body temperature was dropped to
26 degrees Celsius then they opened the chest, clamped the vena cavas for 5.5 minutes and
corrected the atrial septal defect. The child was discharged 11 days postoperatively (Braile, D., &
Godoy, M. , 2012). This was the first open-heart surgery performed successfully in the world and
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a major turning point for cardiac surgeries. With this turning point, surgeons were anxious to
operate on patients and to experiment with new ideas and research.
Munos, E., Calderon, J., Pillois, X., Lafitte, S., Ouattara, A., Labrousse, L., and
Barandon, L. (2011), described the On Pump Beating-Heart (OPBH) surgery that was introduced
in the 1990’s. With this technique, surgeons could perform a Coronary Artery Bypass Graft
(CABG) using systemic extracorporeal circulatory support and avoid clamping. Prior to the
introduction of OPBH, the most accepted way to perform a CABG was the Conventional
Extracorporeal Circulation (CECC). It was safe and there was a low mortality rate, however the
procedure posed a few negative effects, such as stimulation of a systemic inflammatory response,
neurological disorder, coagulopathy and multi-organ dysfunction. To improve these negative
effects, Off-Pump Coronary Artery Bypass (OPCAB) surgery was introduced in the 1990’s.
Minimal Extracorporeal Circulation (MECC) was also developed in with the hope of improving
the negative effects of CECC. MECC involves a closed, fully heparin-coated system with a short
tubing length, integrating a membrane oxygenator and a centrifugal pump (Munos et. al 2011).
This technique is more biocompatible, but CECC was still being used more than MECC. In
previous studies, these different techniques were already studied but using low-risk patients.
Authors hypothesized that OPBH surgery (with an MECC support system) for CABG in highrisk patients with severe co-morbidities would have a better outcome than CECC (Munos et. al
2011). In this study, the authors measured the results of OPBH compared to OPCAB, MECC and
CECC in very high-risk patients. The participants in this study had to have a combination of at
least two the following: over the age of 75, morbidly obese with a BMI of greater than 30%,
severe left ventricular dysfunction <30%, peripheral vascular disease with ankle brachial index
<0.9, severe chronic renal disease with clearance <40 ml/min, acute myocardial infarction or
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recent infarction, and severe chronic obstructive pulmonary disease (COPD) (Munos et.al 2011).
The study design separated CABG surgery techniques into four groups: OPCAB surgery, OPHB
surgery using MECC, CABG surgery using MECC with cardiac arrest, and CABG surgery using
CECC with cardiac arrest. The object of the surgery was to revascularize the coronary arteries.
The study was performed from January 2008 to January 2010. The selected sample consisted of
214 patients that underwent CABG surgery. OPCAB technique was used to operate on 57
patients, OPBH technique was used to operate on 51 patients, MECC technique was used on
another 51 patients, and CECC technique was used on the last 55 patients.
Munos’ et. al (2011) preoperative data findings showed the following:
The average of number of CABG per patient and cases of planned revascularization were
significantly reduced in the OPCAB group compared to the three other groups. In the
same way, incomplete revascularization was significantly higher in the OPCAB group
compared to the others. In the three groups using cardiopulmonary bypass, bypass time
and average number of grafts were no different. Finally, in the OPBH group, the
possibility of offering a complete and planned revascularization was the same as in the
MECC and CECC groups and higher than in the OPCAB group (p. 126).
Munos’ et. al (2011) postoperative data findings showed the following:
The average length of ICU stay was 2.53 ± 1.59 days, with a significant reduction in the
OPBH group (2.16 ± 1.36). Postoperative cardiogenic shock was 6.5% and the necessity
for an intraaortic counter pulsation balloon (IACPB) was 6.1%. Postoperative myocardial
infarction was observed in 5.1% of cases. In all, 27.6% of patients required
administration of cardiotonic agents (dobutamine, milrinone, and norepinephrine) in the
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postoperative period. Compared to the OPCAB, MECC and CECC groups, the incidence
of cardiogenic shock (2% vs. 8%, p<0.05), the use of cardiotonic agents (15.7% vs.
31.3%, p=0.03) and positioning of the IACPB (0% vs. 8%, p<0.05) was significantly
reduced in the OPBH group. Only 23.5% of patients needed diuretics in the OPBH group
compared with 45% in the three other groups (p. 127).
These findings support the hypothesis that OPBH surgery technique would have a better
outcome than previous techniques. The study showed that it was possible, in very-high-risk
patients, to carry out revascularization similar to that using MECC or CECC under cardiac arrest.
Revascularization was more complete when using the OPBH technique than using the OPCAB
technique. Maintaining circulatory support without myocardial ischemia reduces hemodynamic
instability and prevents multi-organ ischemia, which is responsible for severe dysfunctions
(Munos et. al 2011). The limitations of this study were the sample size. It was relatively small,
and it was single-centre and non-randomized study.
Shortly after, the topic of minimally invasive operations in cardiac surgery arose. There
were many benefits to minimally invasive operations, such as smaller incisions, less pain, shorter
length of stay, and quicker recovery to preoperative functional activity level. Kitamura, T.,
Edwards, J., Worthington, M., Rathore, K., Misra, M., Slimani, E., and Stuklis, R. (2010)
described the benefits in cardiac surgery. The purpose of this study was to analyze the experience
with minimally invasive mitral valve surgery. This study was taken place in a public teaching
hospital in Australia. 60 patients from November 2006 to March of 2009 underwent minimally
invasive valve surgery with a videoscope. These 60 patients were the subjects of this study.
Mitral Valve Plasty (MVP) was performed on 47 patients and Mitral Valve Replacement (MVR)
was performed on 13 patients. According to Kitamura et. al (2010), the result findings showed
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that aortic cross-clamping was not applied in seven surgeries, in which six surgeries were due to
reoperation and one surgery had too severe chest deformity. The average times for
cardiopulmonary bypass (CPB) was 140 ± 46 minutes and aortic cross-clamp was 93 ± 35 min.
MVR showed shorter times compared to MVP when using CPB and aortic cross-clamp
techniques.
Kitamura’s et. al (2010) study also found the following:
There were no operative deaths among the entire cohort. Reoperation for bleeding was
required in two patients, both of whom had undergone MVP. Permanent stroke was
observed in two patients, one of whom required 8 days of ventilation time and the other
required 39 days of ventilation, but the average ventilation time was 14 ± 10 h. The
mean intensive care unit and hospital stays for the entire cohort were 3.1 ± 5.8 days
(range 1–43 days) and 10.6 ± 8.9 days (range 4–60 days), respectively (p. 570).
More findings showed that approximately 12 months postoperative, out of 34 of the 47 patients
who underwent MVP, 11 patients had worsened mitral regurgitation (MR). MR was unchanged
in 21 patients and MR improved in 2 patients. This study showed promising results of this new
technique, thus surgeons started performing this minimally invasive technique. The limitations of
this minimally invasive technique, were that this study was a small number, retrospective study,
and that it lacked a control group of conventional mitral valve operations for comparison
(Kitamura et. al 2010).
A new minimally invasive operation was introduced shortly after the videoscope. Robotic
cardiac surgery emerged. The da Vinci surgical system is the only system approved by the US
Food and Drug Administration (FDA) to be used in cardiac surgeries. The da Vinci™ surgical
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system provided increased operative dexterity for surgeons. The wrist-like articulating
instruments move with six degrees of freedom, offer tremor-free movements, ambidexterity, the
avoidance of the fulcrum effect, and improved operative visualization greatly through the use of
three-dimensional high-definition imaging. (Bush, B., Nifong, L., & Chitwood Jr., W. (2013).
Bush et. al 2013, described different studies of the use of the da Vinci surgical system. The Total
Endoscopic Coronary Artery Bypass Grafting (TECAB) is the first generation of da Vinci
surgical system, which was used in a trail in 2006. 98 patients who required revascularization of
the left anterior descending artery was used in this study, and the patients were enrolled at 12
different centers. 13 patients were excluded from this study due to different reasons not listed. Of
the 85 remaining patients who underwent a TECAB, there were 6% conversions to an open
sternotomy, no deaths, no strokes, one early reintervention, and one myocardial infarction. (Bush
et. al 2013).
Bush et. al (2013) described another study with 86 patients who underwent Robotic
mitral valve repair, which is the most commonly used robotic assisted cardiac surgery, with
concomitant cryomaze. This technique positioned an 8- cm flexible argon-cooled flexible probe
with robotic forceps. 83 patients were absent of atrial fibrillation during the follow-up period of
351 ± 281 days postoperatively (Bush et. al 2013).
Bush’s et. al (2013) study findings also showed the following:
Cardiopulmonary bypass procedure times were longer when cryoablation was added to
lone mitral valve repair (189 minutes versus 153 minutes). Cross-clamp times were also
longer (131 minutes versus 117 minutes). The robotically assisted, right minithoracotomy approach may prove to be an ideal minimally invasive surgical treatment for
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atrial fibrillation, whether combined with mitral valve surgery or done as a stand-alone
operation (p. 5).
The TECAB approach has shown to decrease pain, smaller incisions, and improved cosmesis.
Even with these benefits there were still several limitations. Surgeons remained concerned about
the lack of haptic feedback, which was not a concern for these studies. The authors believe that
future robotic systems will likely incorporate strain sensors to the instrument arms, allowing for
haptic feedback and precise control of force (Bush et. al 2013).
After the surgery, next was the tissue of postoperative care. Goldie, C. L., Prodan-Bhalla,
N., and Mackay, M. (2012) described the role of the nurse practitioners in postoperative cardiac
surgery in Canada. Acute care nurse practitioners (ACNPs) are in high demand in Canada due to
the decreased of medical residents and staff physicians. ACNPs were known to provide enhanced
education and communication between healthcare providers and family members. The purpose
of this study was to compare the effectiveness of ACNP-led care to hospitalist-led care in a
postoperative cardiac surgery unit in a Canadian, university-affiliated, tertiary care hospital
(Goldie et. al 2012). Hospitalists were physicians trained in general practice. This study took
place in a postoperative cardiac surgery unit at a large, tertiary-care Canadian hospital. Little
research on ACNP roles in Canada had been done in the past. In previous studies, researchers
compared the effectiveness of ACNP led postoperative care versus physician led postoperative
care in an acute care hospital. The results showed no differences in patient outcomes, such as
morbidity, mortality or length of hospital stay. The results of the previous studies also showed
that patient satisfaction was greater in the ACNP group than the medical staff. Another study
performed by Meyer and Miers in 2005 compared ACNP provided care in collaboration with
cardiovascular surgeons or a cardiologists versus cardiovascular surgeons or a cardiologists care
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alone. They found that when cardiovascular surgeons directed postoperative care in collaboration
with ACNPs, the average length of hospital stay decreased by 1.91 days and average total cost
decreased by $5,038.91 (U.S.) per patient, compared to surgeon-only care (Goldie et. al 2012).
The framework of this study was developed by Sidani and Irvine in 1999. Two
components were used as the design of this study. The first component was the structure
component which included the patient, the ACNP and organizational variables. The second
component was the process component, which consists of ACNP role components and role
enactment (Goldie et. al 2012). The authors hypothesized that patient outcomes would be more
favorable with the ACNP provided care over the hospitalists provided care. Two specific
questions were addressed to guide this study. First, is there a difference in ACNP-led versus
hospitalist-led postoperative cardiac surgical care with respect to the following patient outcomes:
a. hospital length-of-stay b. rates of readmission to hospital c. selected postoperative
complications d. adherence to follow-up with family physician and cardiologist e. cardiac
rehabilitation attendance? Second, is there a difference in patient or health care team satisfaction
with ACNP versus hospitalist-led care in a postoperative cardiac surgery program (Goldie et. al
2012)? The participants for this study included patients 18 years of age or older who had been
scheduled for CABG between May of 2004 and February of 2005. Participants must be able to
read and understand English. The ACNP had approximately 10 patients during a day and
developed individualized care plans for each patient. After discharge, the patient was sent a letter
survey about hospital stay and recommendations. Initially, there were 103 participants, with 81
in the hospitalist-led group and 22 in the ACNP-led group. 26 participants in the hospitalist-led
group were lost in follow-up and 5 participants in the ACNP-led-group were lost in the followup.
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Goldie’s et. al (2012) clinical outcomes were as follows:
The ACNP- and hospitalist-led groups did not differ significantly in length of hospital
stay, hospital readmission within 60 days, number of postoperative complications and
attendance at cardiology or cardiac rehabilitation appointments. However, significantly
more individuals in the hospitalist-led group attended their family physician follow-up
appointment within a week of discharge (p. 12).
Also, the overall patient and team satisfaction did not differ significantly. However, ACNP-led
care was rated significantly higher on several patient satisfaction items (relating to teaching,
answering questions, listening and pain management) ( Goldie et. al 2012). What surprised
researchers were that the ANCP-led group had more complex participants with complicated
surgeries than the hospitalist-led group yet there was no significant difference in outcomes.
Goldie’s et. al (2012) conclusion and limitations are as follows:
The findings of this evaluation of the ACNP practice in a postoperative cardiac surgery
unit indicate that the ACNP role is effective in this setting and patients are satisfied with
ACNP-led care. Further research is required to replicate these findings in other
postoperative cardiac surgery units with larger sample sizes and validated measures.
Larger studies will increase our understanding of ACNP practice in Canadian acute care
settings (p. 14)
Lastly, after a major cardiovascular event, in which a patient undergoes surgery, the
transformation from hospital to home has always been an issue. Patients experience many
problems regarding the outcome of the disease or rehabilitation including concern about the
return to their previous life. Recovering from a cardiac event is a complex procedure that
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presents psychological and physical needs that continue after discharge from hospital (Kadda,
O., Marvaki, C., and Panagiotakos, D. 2012). Nurses represent a large percentage of the health
care in the community. They play a vital role in treatment because they communicate and care
for the patients and their families during the process of the disease. It is vital for nurses to meet
the rehabilitative care needs of patients through education, support, supervision and
reinforcement. A health educational program organized by nurses for patients after a cardiac
event or surgery improves patients’ knowledge of their illness and awareness of behavioral
changes. This type of education would help in the effort to prevent a new event or readmission to
hospital.
In conclusion, with heart disease been the leading cause of death in the United States, one
would expect an increase in cardiac surgery operations. Robotics in surgery is the future of
medicine. Surgeries have become less invasive while leaving smaller incisions. Also, surgery
time has been shortened, the length of stay has decreased, and the mortality rate has declined
with the use of robotics. While nurses represent a large percentage of health care in the
community, the role of a nurse is suspected to gear more towards education. Educating the
community on ways to prevent heart disease, such as smoking cessation, nutrition counseling,
and proper exercise, is paramount in reducing the prevalence of heart disease. Cardiac surgery
has evolved tremendously from the 19th century to present day because for those daring surgeons
who did not allow the criticisms stop them. More research is being done, more surgeons are
experimenting, and cardiac surgery is expected to improve over the next decade.
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Bush, B., Nifong, L., & Chitwood Jr., W. (2013). Robotics in Cardiac Surgery: Past, Present, and
Future. Rambam Maimonides Medical Journal, 4(3), 1-8.
Chitwood Jr., W. (2011). Robotic Cardiac Surgery by 2031. Texas Heart Institute Journal, 38(6),
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Ellis, H. (2011). The early days of heart valve surgery. Journal Of Perioperative Practice, 21(8),
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Goldie, C. L., Prodan-Bhalla, N., & Mackay, M. (2012). Nurse Practitioners in Postoperative
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